Kicking it up with 3D printing in the textile industry at ITMA 2023

The ITMA 2023 show in Milano showed that digital knitting is the future of wearables and that includes footwear as well as different types of garments. ITMA is the world’s most influential textile and garment technology exhibition. Owned by CEMATEX, it is the place where the industry converges every four years to showcase the latest textile and garment processing technologies, machinery and materials, promote collaborations and forge partnerships. This year three specialized AM companies, HP, Stratasys and CeramTec, participated as exhibitors, focusing on very different aspects of the textile supply chain. But they were certainly not the only ones that used AM at some level, among 1,709 exhibitors from 47 countries, occupying 200,000 square meters of gross exhibition space.

Mr. Federico Pellegata, director of the Italian association ACIMIT, noted: “The results of the Milan edition confirmed ITMA as the most important showcase for the world textile machinery industry. It was a great success, judging from the quality of visitors in attendance, and many Italian exhibitors have secured contracts and sold their machines.” The global textile machinery industry is large – we are talking $26.2 billion by some estimates – and growing to over $40 billion by 2030. Opportunities for AM in the textile industry are significant. Let’s take a closer look.

While it is certainly a digital manufacturing process, digital knitting is not considered to be an additive technology. It is simply a more automated version of knitting and it can leverage consolidated practices and materials. We’ve seen 3D printing being used for insoles, midsoles and in some cases even for outsoles but the biggest challenge is the uppers. Traditional upper manufacturing 2D prints colors and TPU reinforcements on a woven sheet that needs to be cut and sewn back together. That’s why some explore the possibility of introducing 3D printing technology to automate upper manufacturing but digital knitting is proving much more effective. In this case, 3D printing can provide the perfect combination of a generatively optimized, mass-customized sole that just needs to be combined with the upper for a finished product.

That’s exactly the concept that HP 3D Printing, in collaboration con Lonati Group and Decathlon showed at ITMA 2023. Together, they present an innovative and sustainable approach to shoe manufacturing that has the potential to reshape the industry. Traditionally, shoe production requires numerous parts, adhesive materials, and a significant workforce. This shoe combines Lonati’s digitally crafted sock with an innovative midsole and outsole produced using HP’s Jet Fusion 5200 3D printer for series production. Lonati’s XT-MACHINE and Double Cylinder E1530XS knitting machines allow the production of shoe uppers with single or double-layer fabric – resulting in an integrated upper that ensures comfort, lightness, performance, and quality.

The components are manufactured using BASF Ultrasint TPU01 material, a thermoplastic polyurethane powder known for its shock absorption and flexibility. By integrating these materials and technologies, Decathlon and HP are focusing on the advantages of 3D printing and digital knitting for manufacturing at an industrial level, emphasizing customization, circularity and repeatability, localized production, and flexibility. By utilizing a glue-free assembly method, the shoe can be easily repaired when damaged. The cushion and upper parts can be separated, allowing for targeted repairs without the need to discard the entire shoe. This not only extends the lifespan of the product but also reduces waste. Moreover, the use of a single material, TPU, for the grip and cushion parts enhances the shoe’s recyclability. All of this contributes to a more sustainable and environmentally friendly product life cycle.

Decathlon developed an app to customize the sole to each user and type of use and the company intends to bring this product to market. A lot will depend on the cost per part that they will be able to achieve. Today a 3D printed sole (midsole and outsole) could run about $25, which is still high for a serially manufactured product but could be within reach for a custom, high-performance product.

Stratasys – via the Italian Stratasys branch – leveraged ITMA 2023 to show off its unique TechStyle technology for 3D printing on textiles. This technology is looking specifically at the fashion market and was first presented during Milan Design Week in 2022. Using a J850 system, the process enables actual 3D printing of full-color, polyurethane-like decorations and decorative items of different elasticity.

“It enables something that no one else in the textile industry can do and everyone wants,” says Fabio Boiocchi, Marketing Manager Italy at Stratasys. “The attention from the textile industry has ben enormous. Not just from shoe and garment makers but from all types of companies. I am certain that we will see many interesting projects emerging in the near future.” While it is unique and is becoming more accessible, TechStyle technology remains mostly experimental as it requires a specially made J850 system along with Strastasys’ unique resins. However, its value proposition is valid, especially for high end uniquely customized products, and these large potential adopters now need to demonstrate production applications.

Stratasys is providing designers and fashion brands with the ability to differentiate their manufacturing practices through the unique versatility and productivity of the Stratasys 3DFashion solution which includes the J850 TechStyle 3D printer, workflow software and materials that support the individual needs of fashion manufacturers. This solution opens unlimited possibilities for fashion manufacturers to personalize and customize 3D printed fabric pieces – including limited editions and digital automation, all while reducing time-to-market and ensuring mindful manufacturing.

The J850 TechStyle 3D printer is designed to print directly on a variety of fabrics and garments, including denim, cotton, polyester, linen and leather at volumes ranging from single pieces to tens of thousands.

State-of-the-art 3D printed shoes and multi-color 3D printing on textiles are fascinating, however the most important, short terms commercial applications for 3D printing in the textile industry may appear a little bit more “boring”. Yet, the ability to 3D print specific parts for automated textile and digital knitting machines is truly opening a new era in the industry as companies rapidly develop new and more efficient systems.

This is happening at many levels and with many different technologies. In fact, the first booth we saw when entered the ITMA 2023 fair was Colosio, another company that develops high-tech machines for 3D shoe-uppers production. On display were a few prototypes that combined the digitally knitted uppers with clearly 3D printed soles. Project Manager Cesare Colosio explained that they actually use 3D printing primarily for machine parts and showed us several in the newest S1M system that was printed using a filament extrusion machine. More complex PBF parts are obtained via external 3D printing service providers however the company is also considering acquiring a machine for internal use.

When it comes to PBF machine parts, HP’s MultiJet Fusion is one of the most widely used technologies. At the Lonati booth, Stefania Minnella, Applications Specialist, and Davide Ferrurlli, Regional Manager of Southern Europe, showed us several 3D printed parts, including grippers and connectors, in the Lonati machine used for the Decathlon project.

The most interesting and somewhat unexpected new application, in terms of machine parts, came from CeramTec, a German company that is emerging as a leader in the development of new technical ceramic 3D printing applications. In 2021, CeramTec implemented a binder jetting process for the production of construction elements made from a new SiSiC technical ceramic. More recently the company acquired a Carmel system from XJet to 3D print alumina parts, specifically for machines such as those in the textile industry, where CeramTec is already present as a key part supplier.

The company is getting a head start on the future of part manufacturing to meet the constantly evolving part requirements from companies in the textile industry. Now the challenge is to identify all the applications that can benefit from the advanced geometries that are possible only with AM. For that, CeramTec offers free consultancy sessions to interested parties. The time has come to hit the ground running.