Hanover, March 2010 – When Continental starts brewing up a storm and the rubber gets to bubbling, something round is bound to come out of it all. In the making, in effect, are high-tech tires – for cars as well as trucks – based on complex recipes. Complex is the right word, indeed, for a tire consisting of no fewer than fifteen rubber compounds, the composition of which is a closely guarded secret. The aim of modern tire production at Europe’s leading car tire manufacturer is – among other things – to abandon fossil raw materials for alternative rubber and recycled materials. For more than ten years now, both natural oils and reprocessed oils have been employed. With a view to the future, Dr. Boris Mergell, head of car and truck tire material and process development at Continental, notes: “We are currently in the process of putting together a prototype tire that gets by without fossil raw materials more than 90 percent of the way." Of one thing Mergell is certain, though: Even in the case of this new "green" tire, the color is going to be black.

Car tires are two-thirds rubber. A large share of the rubber portion is made from renewable raw materials extracted from Central American rubber trees, which, however, are also cultivated in Asia, expressly for natural rubber production. In the case of truck tires, the natural rubber portion of the overall rubber content is as high as 80 percent. Thailand, Indonesia and Malaysia are among the major suppliers of natural rubber. Roughly 20- to 40-meter-high rubber trees with a circumference of about 35 centimeters grow there. To extract natural rubber, incisions are made into the five- or six-year-old trees with a special knife so that the trees can be “milked”. To do this, a small pail is positioned under the incision. The latex dripping out of the incision into the pail is subsequently processed into natural rubber. At the age of 25 the tree ceases to produce latex. It is then felled and replaced by a sapling. The wood, which is harder than beech, maple or oak, is frequently used to make furniture but is also good for toys or musical instruments. Most of the rubber plantations belong to small-scale farmers. International companies maintain very few plantations of their own.

Inside the tire, Continental uses recycled steel to reinforce the belt. Textile cord materials are also increasingly being replaced by recycled products or by products made of renewable raw materials – like rayon. The best thing about all of this is that tires with this kind of “ecological” reinforcement material are ten percent lighter than conventional products. This helps reduce the overall weight of a car, so it requires less fuel to get about. Mergell: "We are aiming to become even more sustainable, both with respect to the raw materials we use and in production."