Since launching its Wool Runners in 2016, Allbirds has made its name on the sustainable materials that brings its footwear and fashion to life, turning out everything from sugarcane shoe soles to sea shell sweaters.
The popular DTC brand will soon add plant leather to its growing suite of eco-materials, thanks to a $2 million investment it made in Natural Fiber Welding (NFW) late last year.
Allbirds plans to launch the first shoe using the materials developer’s Mirum technology in December. NFW founder and CEO Luke Haverhals declined to name the specific shoe Allbirds will use for its debut plant leather product, but indicated that it will be one of the brand’s “classic silhouettes.”
“After reviewing many other technologies, we found NFW to have the key combination of innovation, carbon reduction capability and scalability that we knew was critical for success in a leather alternative,” Claudia Richardson, senior manager of material innovation at Allbirds, told Sourcing Journal.
The material, made from a mix of vegetable oil, natural rubber and other bio-ingredients, will use 17 times less carbon than synthetic plastic-based leather and have a carbon impact 40 times lower than traditional leather, according to Allbirds. Looking to the years ahead, Richardson said Allbirds expects plant leather will become one of its core platforms, similar to its merino wool and eucalyptus tree-based materials.
Haverhals said NFW differentiates itself from the other plant-based leather makers out there by completely cutting out plastics, including polyurethane and other kinds of petrochemical plastic-based coatings.
“NFW is just categorically unique in that we’re launching what we understand, or at least what customers tell us, is the world’s only zero-plastic leather alternative,” Haverhals told Sourcing Journal.
Richardson said it was this non-reliance on plastic coatings and synthetic materials that attracted Allbirds to NFW. “We’ve always wanted to eliminate petroleum from the fashion industry and we’ll only be able to do so if we find new processes and materials that can be replicated and repeated easily,” she added. “With their new Mirum technology, we’re looking at potentially an over 95 percent reduction in carbon emissions versus animal leather, which could truly be game changing for the fashion industry and beyond.”
Haverhals also touted Mirum’s recyclability. Though its lack of plastics would allow someone to “grind it up and return it to the Earth,” as Haverhals put it, NFW developed its plant leather so that it can be recycled. “There’s some additional special things about the formulation that allows us to take the scrap, for example, and turn it back into new,” Haverhals said.
NFW looks beyond Allbirds
Though Allbirds has received lead time on using NFW’s Mirum product, it is not the only brand the company is working with. All told, Haverhals estimated there could be more than a dozen other companies sending products to market with NFW’s plant leather in 2022.
The type of shoe the firm’s Mirum material can work with “is pretty wide,” Haverhals said. “Of course, there’s formal wear and streetwear. And there’s the difference between work boots and stilettos…. The technology is extremely tunable. Our ability to tune for not only mechanical performance, but aesthetic is very broad and gives us certain advantages in working with a breadth of different kinds of brands and different kinds of products.”
This tuneability also allows NFW’s partners to weigh durability and sustainability as they see fit. “One of the things that makes plastics great but also not so great is that sometimes they’re too durable, they don’t break down when you want them to,” Haverhals said. In Mirum’s case, NFW can adjust the durability of its leathers to match their specific applications, whether that’s for a pair of shoes or simply a wallet.
“Does the customer want to build a timeless thing that lasts and lasts and lasts or do they want to build something for the circular economy that’s made to be obsoleted in a couple years but it’s okay because NFW can turn it back into dirt or turn it back into product,” Haverhals said.
At the same time Allbirds invested in NFW last year, Ralph Lauren was putting forward its own money to help fund Clarus, another material the startup is developing that reuses natural fibers such as cotton waste to create more durable, high-performance materials and goods. Thanks to these twin investments, NFW has been able to double its employee staff to 100 with plans to hit 250 by the end of the year. “We’re on a very steep ramp right now,” Haverhals said.
Clarus and Mirum, both heading to market now at the same time, are simply NFW’s first two products. Haverhals said the company is also looking to bring several others, such as water-repellant materials and foams, to commercial scale in the future.
“Think of all the different materials that you might find if you slice your shoe in half and tried to figure out what’s all in there,” Haverhals said. “We are saying that we are plants, not plastic. It’s not plants, not one kind of plastic, it’s plants, not all kinds of plastics. It means an ecosystem.”