Published On: Mon, Jul 25th, 2016

These cute 3D knitted flats are made from recycled water bottles

It seems that San Francisco based footwear company Rothy’s is hoping to get shoe lovers and fashionistas on board with sustainable fashion with their latest collection of flats made from, believe it or not, recycled plastic bottles.

Of course, clients won’t be wearing water bottles on their feet like you may be imagining, as the company has integrated a processing method that turns PET plastic bottles into plastic yarn that can be 3D knitted into the form of the shoe.

plastic processing

These cute 3D knitted flats are made from recycled water bottles

The shoe collection, which features two styles (Flat and Point), was made using a proprietary process that involves turning PET plastic bottles into a knittable plastic yarn. More specifically, the process consists of removing caps and labels from the bottles, hot-washing them, cutting them into flakes and then melting them down into a filament fiber, which is finished with a wicking agent to keep the shoe material as moisture-free as possible. The yarn is then knitted into the upper shoe shape with Rothy’s 3D knitting machine, a process which reportedly takes only six minutes, and the shoe is set using heat and a shoe mold. According to the company, each pair of shoes uses about three recycled plastic bottles.

Researchers at Rothy’s have been working for three years to develop the fully recycled and recyclable shoe. In addition to the 3D knitted upper part of the shoe, which encases the wearer’s foot, they have also developed carbon-free rubber outsoles, and recyclable foam insoles. To top it all off, when the wearer has no more use for the shoes they can also be recycled by simply sending the worn pair to PLUSfoam, which has collaborated with Rothy for the collection.

Roth Martin, cofounder and Chief Creative Offiver of Rothy’s says, “You have a tremendous amount of scrap waste that’s going into landfills. Our process allows us to knit three-dimensional parts that use the exact amount of material that they need to use in order to create the part. So, like an inkjet printer, it draws just the amount of ink that it needs to complete that task, and then it repeats the task as needed.”

As mentioned, Rothy’s shoe collection is available in two different styles and comes in 17 different color combinations, including solid and camo prints. A pair of Flat shoes is retailing for $125, while the Point style is marginally more expensive at $145. If you’re still wondering how a shoe made from recycled bottles could possibly be comfortable, Martin assures that they are saying, “There’s no elastic in it, and no seams. So your foot’s in contact with one material, which is novel in itself. And because of the knit structure, it has a nice give to it that holds its shape beautifully.”

3D knitting technologies have also taken off elsewhere, for instance with Nike’s innovative FlyKnit sneakers, which boast as little as one thimble full of material waste from their production. Unlike traditional shoemaking techniques, which often result in excessive material waste from cutting out the various shoe parts, 3D knitting, especially with a fully recycled plastic yarn, offers a much more sustainable manufacturing approach.