If it were up to TU/e researchers Troy Nachtigall and Oscar Tomico, future wardrobes will be characterized by aquariums with 3D-printed shoes in a bath of biomaterials, such as kombucha. That fermented, healthy hipster drink is a good example of a natural product that can also be used to grow organic soles around footwear. A sustainable alternative to plastic or rubber that can be replaced repeatedly after wear and tear. Prototypes of such 'living fashion' can be seen during the current Dutch Design Week .
'Minister gets 'no blisters' from printed shoe'. That was the headline ten years ago above one of the many articles about the innovative outfit of then Minister of Education Jet Bussemaker during Dutch Prinsjesdag. The 3D printed shoes, dress, and bag she wore were designed by the TU/e research group Wearable Senses. In the fashion world, which revolves around lightning-fast trends and continuous change, ten years is an eternity. Yet in 2025, you will hardly find 3D printed items in the average wardrobe.
Ten years ago, it took more than four days to print a 3D shoe, now it only takes one day.
Assistant Professor Troy Nachtigall
It is certainly not due to science that this is not yet commonplace, emphasizes Troy Nachtigall , who as a PhD student in 2015 worked on Bussemaker's innovative Prinsjesdag look. At the time, he was mainly concerned with the 3D printed shoes, with which he ventured into uncharted territory. In the meantime, he was promoted to research professor at the Hogeschool van Amsterdam and assistant professor at the TU/e department of Industrial Design, and is still fully involved in Wearable Senses.
New printing techniques
"We have continued our research into 3D-printed shoes and developed new printing techniques. Ten years ago, it took 4.5 days to print a shoe; now it takes only 1 day. Other technological developments are also taking us further and further ahead. Biotechnology in particular is promising these days."
Nachtigall found a partner in fellow researcher Oscar Tomico , associate professor with an expertise in "Multispecies sustainability" (designing for cohabitation with other living beings, e.g. plants). Together they are working on 3D-printed shoes with organic soles that can be changed or renewed every time.
Customization for the masses
This is not only more sustainable, but it also offers countless possibilities to create your own shoes completely according to your wishes. Such customization is an important motivator to embrace innovation in the fashion world; literally making clothes and shoes on someone's body, as in haute couture, is only accessible and affordable for the happy few. But if technology allows for customization for the masses, everyone can create the best-fitting shoes and clothing for themselves.
3D-printed shoes are slowly but surely becoming mainstream.
Assistant Professor Troy Nachtigall
Now that 3D printing techniques are becoming faster, more accessible, and more affordable, Nachtigall predicts the next fashion revolution is just around the corner. "There is finally momentum for 3D-printing in the shoe market. Several companies have been specializing in it for a while, and big brands, such as Nike, are also seriously interested. It is slowly but surely moving towards the mainstream."
In an article about the revolution of 3D-printed shoes, Nachtigall said that consumers are still waiting to see what happens. "The added value of a 3D printed shoe is not yet clear enough, but that will change thanks to data science and machine learning," he predicts.
Individual comfort
"Walking is quite complex, and comfort is key. Computational manufacturing makes it possible to design not only according to the shape of a foot but also to the weight and pressure profiles of an individual." So, will sneaker freakers soon be able to have personalized Nike or Adidas shoes printed on demand? It won't be that fast yet, Nachtigall suspects.
"The big manufacturers are still in an industrial system that suits them well at the moment. They use the least expensive materials that only last nine to twelve months, so people need to keep consuming. Also, these cheap materials are mixed, making it impossible to recycle the shoes. This way, the industry is creating ecological disasters."
"But there are more and more disruptors on the market, like Zellerfeld , that are working on improvements in the behavior, suspension, and flexibility of 3D-printed shoes. This brings verifiable standardization into view, and then it becomes commercially interesting."
Bio insoles with kombucha
So it's time for the next scientific steps, such as the biosoles from Nachtigall and Tomico. "We understand better and better how to grow biological materials in combination with the structure of a 3D-printed object, in our case, a shoe," says Tomico.
This is how the researchers came up with the wildly popular drink kombucha, which is hyped for its super healthy properties. These arise from the fermentation process that takes place when a bacterial culture is added to the (originally Korean) sweetened black or green tea.
After about a week, a fungus-like skin forms on top of the drink called the kombucha fungus or SCOBY (Symbiotic Culture Of Bacteria and Yeast). In the case of the drink, that SCOBY is filtered out, in the case of the biosoles, that fungal layer is the main player.
You can grow such a biological layer around the same shoe over and over again. You just put it back in the kombucha.
Assistant Professor Troy Nachtigall
"Normally, the production of a shoe sole requires three different types of plastic, depending on structure, performance, and design," Nachtigall explains. "In 3D-printed shoes, it becomes more complicated, because the material is made of one piece. But different parts of shoes have different functions and characteristics, to fit the specific aspects of a foot and the walking process."
"So if we move towards using just one material, it needs to serve all these different characteristics. Which makes it very interesting to design, but also a big challenge. Especially if we want to achieve our ecological goals. We still have a lot of work to do. It's definitely not a finalized product yet, though persistence and new insights are helping us to move forward."
"Wear and tear, in particular, is a difficult factor because you can repair a conventional sole thanks to those different elements. You would have to print a 3D shoe over and over again, which is, of course, not sustainable. But you can grow such a biological layer around the same shoe over and over again. You just put it back in the kombucha."
Living organism
"In this way, part of the shoe consists of a living organism," says Tomico. "Hopefully, that will also change how we look at garments and interact with them. For many people, they have become disposable items, produced quickly and as cheaply as possible, of poor quality, because we only wear them a few times anyway."
"Then they are discarded and end up on the waste mountain or in the incinerator. Would we do the same with living beings? Suppose you considered items of clothing to be your friends, would you treat them just as badly?"
Integrating biology is a necessary development as far as we are concerned.
Associate Professor Oscar Tomico
According to Tomico, living fashion is the next big shift in the fashion industry. "Technology has brought about various cultural changes, but it has also created new challenges. The current massiveness and turnover rate of clothing make the system unsustainable; we are depleting the earth. Integrating biology is, therefore, a necessary development as far as we are concerned."
Fungi at work
Production as part of the ecosystem, the researchers call it. 'Making with' is, therefore, the name of their research group. "How great it would be if in the future we share our homes with fungi and bacteria that continuously make our things for us," Tomico daydreams out loud. "Our houses become places where different species live, with which we form a bond. This also makes us understand and appreciate the production process again."
Nachtigall adds: "It takes about two weeks to form a sole with kombucha. When you literally see that happening in your own home, your view of a new pair of shoes also changes. 'I can't wear those white pumps yet, because the fungi are not fully grown'. That is the idea."
Acceleration thanks to AI
Of course, there is still plenty to improve before that dream can become reality. "Just as it took ten years for 3D printed shoes to go mainstream, this new development also takes time," Nachtigall emphasizes. Luckily, the rise of AI could just accelerate everything. "Through sensors in the sole of your shoe, you collect new knowledge everywhere you walk that can create unprecedented new possibilities through AI."
"Data science helps deal with complexity and customization. Not only by mapping the individual behavior and body type of the shoe wearer, but also because of new options for taking care of your shoes. Like the apps we already have for plants, with which you can just point your phone at them to check their needs. If we can do the same with shoes, such an app will function like a shoe doctor. It is a fascinating playing field on which we are far from finished."
We have taken from nature for so long, now it is time to give back.
Associate Professor Oscar Tomico
So the technology is promising, but in the end, it is mainly consumers and producers who have to move with it, says Tomico. "If we start growing our own shoes, the whole economic system will change."
"Shoe brands, for example, will focus more on leasing and maintaining instead of selling. Shops will become places where you get advice instead of stuff. Who knows? However, it starts with us, the wearers of shoes and clothing. We have taken from nature for so long, now it is time to give back. Design research can help to make this shift happen. That's where the opportunities lie."
