The denim industry is increasingly turning to premium fibers that align with its strong commitment to sustainability. Fibers such as linen, wool, and cashmere are being blended into denim to enhance temperature regulation, comfort, and distinctive hand feel. In addition to their functional benefits, these fibers elevate the perceived luxury of denim, encouraging the creation of garments designed to be worn longer and valued more over time.
AMSilk, the German biotechnology company behind advanced materials derived from spider silk–based proteins, believes biotech silk belongs in this premium fiber landscape.
The company recently introduced its spider silk in two fabrics by Italian mill Pure Denim. The fabrics are a 11.2 oz. denim made with 67 percent cotton and 33 percent spider silk, and a heavier 12 oz. fabric made with 59 percent cotton and 41 percent spider silk.
AMSilk was born from the University of Biotech in Munich. For the past 18 years, the company has been taking pure silk protein powder, which is dissolved and then spun into filaments through a wet spinning process, to create 100 percent silk filaments.
At the outset, Benoît Cugnet, AMSilk’s head of fiber, emphasized that the company’s goal was not sustainability. Instead, AMSilk set out to develop a way to cultivate and scale spider silk—an otherwise difficult task, since spiders are territorial and cannibalistic. However, its bacteriostatic and hydrophilic properties made it attractive for applications in the medical and cosmetic industries. By programming bacteria with the genetic code of the spider silk, AMSilk could, for the first time, eliminate the spider through a breakthrough fermentation process that resulted in the first grams of protein coming from the DNA of a spider. Scientist then transformed this pure protein into filament yarn.
“But as we know, especially in luxury, it has to be beautiful as well. So, we are very lucky to have been able to develop very fine filament yarns, which, as you assemble into fabric, woven or knitted, you obtain something which is very silk like in terms of touch and look,” Cugnet said.
It has taken AMSilk about 15 years to reach the multi-ton scale it has today. “It’s been a real long and complex process, but that’s very normal in biotechnology,” Cugnet said.
AMSilk will produce about 30 tons of spider silk this year and it has plans to scale production to 700 tons by 2030. It is currently 30 percent more expensive than traditional silk, but Cugnet expects it to drop as production and market adoption grows.
The company’s current product portfolio ranges from super fine yarns for silk like premium filaments for fashion and accessories to more technical yarns for automotive interiors. When the company looked at which categories would benefit the most from its properties, Cugnet said denim emerged as untapped opportunity.
The benefits of AMSilk in denim are wide sweeping. Spider silk’s bacteriostatic properties inhibit the growth of odor-causing bacteria, keeping denim garments fresher for longer and reducing the need for laundering. This reduces the risk of skin irritation and fabric degradation, preserving garment integrity and appearance. It also enhances breathability and moisture management, allowing moisture and water vapor to escape and keeping the wearer cool and dry.
Additionally, plant-based, animal-free AMSilk aligns with denim companies’ sustainability missions. The company’s recent LCA studies comparing AMSilk to traditional mulberry silk production reveal significant sustainability advantages such as 85 percent lower climate impact and a 97 percent reduction in water consumption and 92 percent reduction in land use.
The ingredient is also fully recyclable, biodegradable and contains no microplastic matter.
Cugnet says the Pure Denim fabrics are receiving enormous interest from luxury brands—for both its newness and for its performance-enhancing properties. “We are struggling even to sample at the moment because interest is so big,” he said.
AMSilk is applied exclusively to the weft, increasing the filament’s contact with the skin. Cugnet noted that the result is a noticeably smoother, softer hand feel compared to 100 percent traditional cotton denim. While denim purists may prefer premium fabrics in their raw state, he added that the AMSilk performs exceptionally well in standard washing and finishing processes, giving designers full creative freedom.
Although silk-blended denim may not be destined for the mainstream, Cugnet emphasized that like biotechnology the denim industry continues to push forward with innovation. “Denim is always being reinvented, and this is definitely a new wave,” he said.
Source: https://sourcingjournal.com/