Continental has unveiled the Conti GreenConcept at this year’s IAA Mobility (also known as the Munich Motor Show), which is a conceptual study that leverages both current and emerging technologies when it comes to engineering sustainable tyres of passenger vehicles.
The goal here is to minimise resource consumption across the tyre’s value chain, and to do so, the study addresses things like the sourcing and procurement of raw materials to the various stages of production, and even the ways to extend the service life of the tyre.
According to Continental, more than 50% of the raw materials used to make the Conti GreenConcept come from either renewable sources or recycled. The company says this is an important step as it aims to fully transition to use sustainable raw materials by 2050. It also defined “sustainable” as being materials that originate from closed-loop cycles, have no harmful effects on people or the environment, responsibly sourced and climate-neutral across they entire supply chains.
Going into detail, 35% of the eco-friendly tyre concept is made from renewable materials, including natural rubber from dandelions, silicate from the ash of rich husks, as well as vegetable oils and resins, all of which reduce the dependence on materials based on crude oil.
The company says its global tyre-making plants are already making widespread use of materials such as recycled rubber or vegetable oils. In addition, it’s also looking to further the cultivation and processing of sustainable materials by working with partners to conduct intensive research into the use of Russian dandelion, which can be grown near its plants to lower carbon emissions from long-distance transport and conserve resources.
Meanwhile, 17% of the Conti GreenConcept is made up of recycle materials like reclaimed steel and recovered carbon black. Furthermore, in an industry first, polyester from recycled PET bottles is also used as part of the company’s ContiRe.Tex technology, which it says will be gradually rolled out from 2022.
The recycling process involving PET bottles doesn’t involve the usual intermediate chemical processing steps, but the resulting polyester yarn is then made functionally capable of handling the high mechanical forces that tyres are subjected to. For some figures, Continental says a typical passenger car tyre consists of roughly 400 grams of polyester yarn, and around 60 recycled PET bottles can be reused to manufacture a set of four tyres.
Continental also worked with Kordsa to develop Cokoon dip technology, which enables eco-friendly bonding of textile reinforcements with rubber compounds. The open-source technology has been made available to all tyre industry players on a free-of-charge basis since 2019.
Besides being more Earth-friendly to manufacture, Conti GreenContact is also 40% lighter than conventional tyres, weighing in at just 7.5 kg. This was made possible by an optimised tread pattern, a special sidewall and a new casing design with a weight-optimised core.
Paired with a specially designed tread that boasts a rolling resistance that about 25% lower than class “A” – i.e., the best possible rating – under the EU Tyre Label system, the tyre concept is capable of providing greater mileage and lower carbon emissions on cars.
To extend the service life of the tyre concept, Continental also engineered it so that it can be retreaded multiple times, with minimal investment in terms of time and materials. On the Conti GreenContact, you’ll find a green-coloured tread baseline that indicates the transition from tread to casing.
Undamaged casings can be resued several times, and as the tread compound is made from 100% Taraxagum natural rubber derived from dandelions, if a tread is renewed three times, for example, this halves the amount of material used for a casing as seen in terms of its total mileage.
