The new sustainable Audi A3 seat covers
89% of the material in the seat covers in the new Audi A3 is made using plastic bottle recycling. How exactly does that work? To find out, we paid a visit to a cloth factory. There, we asked Ute Grönheim from the materials development department how the process could make eco-friendly circular waste management possible at Audi.
You might already have seen shopping bags or clothing made using recycled plastic bottles. But now, at Audi, sustainably produced materials are at the center of the company’s innovations. The potential is enormous: a car contains around 340 kilograms of plastic; about half of that is already recycable. The materials development department at Audi wants to change that. “We want to produce a durable seat cover with outstanding quality that passes all of our product tests — and we want to produce it sustainably,” explains Ute Grönheim. Ute, who has a degree in textile design, is one of the people in the materials development department who is responsible for the seat covers in the new Audi A3. One seat cover is made out of 45 1.5L PET bottles. But what exactly goes on behind the scenes?
From PET bottle to yarn: sorting, shredding, melting
When plastic bottles are returned, the recycling companies reuse only the clear ones. That’s because they’re easier to dye. The lids come off, a bottle washing system washes them. Then a shredder shreds the bottles into little flakes. They are used to make a granulate, which is used by the yarn manufacturer to produce the polyester threads that will later become yarn.
“This granulate is essentially the same as that used for other seat covers, except this is made of recycled PET,” explains Grönheim. Another difference: the granulate is not as evenly milled and pure as the industrially produced granulate. “That can clog up the nozzles in the yarn production. Besides that, the opacity is irregular, so it is less absorbent and needs more dye,” says Grönheim. That’s why it is somewhat more difficult and more expensive to produce recycled polyester threads.
From yarn to seat covers: “warp” speed done differently
The yarn arrives on spools that approximately weigh two kilograms at the tradition-steeped Willy Schmitz cloth factory in Mönchengladbach, Germany. That is where the yarn for the Audi seat covers is processed and made into a fabric. 50 large weaving looms are in the production hall. “The design is transferred onto the loom machine from a USB stick. Then everything runs automatically,” explains Britta Gebhardt, the head of design. The looms hammer, the yarn rushes over the warp beam. It is deafeningly loud in the hall. Two of the machines are weaving the “Torsion” fabric, which will be used in the seat covers of the Audi A3 design selection.
For plant manager Markus Bartsch, it makes no difference whether the yarn they are working with is made of artificially created PET or recycled PET. After it’s been woven, the fabric already looks finished: it has a pattern and already feels like a seat cover. But it’s actually far from finished.
The fabric first has to pass many different quality controls. Yvonne Peschmann carries out the most important one. The experienced fabric mender knows what to look for. With a studied glance, she sees every excess thread. She runs her hands over the fabric to feel for any knots or hard areas. She repairs any small defects immediately with needle, thread and scissors; she marks the larger ones. She checks around 200 meters of cloth per hour this way.
With cloth and fleece to car seat covers
After the quality controls, the fabric is rolled up onto a core and cleaned on a 20-meter long washing system at 60 degrees Celsius. With its multiple washing chambers, the machine manages around 30 meters of fabric per minute. The core holds around 600 meters of cloth. So a washing cycle roughly takes one hour. After it is washed, the fabric is smoothed and dried.
In the next step, a machine glues fleece to the cloth. This process is known as laminating and is important for the seat’s comfort. “Right now we use flame lamination. In this process, an open flame is used to melt a thin layer of foam, which is then glued onto the fabric along with the fleece,” explains Gebhardt. After the fleece is accounted for, the car seat cover is made up of up to 89% recycled plastic bottles. “Our goal for the future is to not only use fleece but also glue that is made of recycled materials,” says Gebhardt.
After a final quality inspection and a stress test, the work at the Schmitz cloth fabric is finished. The cloth for the seat covers in the new A3 hits the road on its way to the next factory. The sewing studio forms the fabric, the upholstery workshop stretches it over the seats. And there it is: the finished, sustainable seat made of recycled PET bottles for the new Audi A3.