Continental: 250,000 tyres with Cokoon produced

Cokoon is the brand name of a new bonding system technology that all tyre manufacturers and their suppliers can use as an open source solution. The development partners, tyre maker Continental and reinforcers manufacturer Kordsa, have chosen to waive development or licensing fees. In return, they expect licensees to make their patents concerning the further enhancement of this technology available to the other partners free of charge via a licensing pool.

The partners began work on this eco-friendly dip technology in 2017, and Continental says it has produced a quarter of a million tyres featuring Cokoon since beginning volume production last year.

Interest from the industry

Prior to Cokoon, the chemicals resorcinol and formaldehyde were irreplaceable in the bonding activation of textile reinforcing materials to the surrounding rubber matrix. Although not harmful to motorists of workers in tyre factories as the substances are chemically altered through the vulcanisation process, the replacement of resorcinol and formaldehyde with more environmentally friendly alternatives is beneficial for a sustainable supply chain as well as for tyre cord manufacturers. Cokoon dip technology makes the bonding of textiles to rubber possible without these two substances, and the technology does not require any changes in process equipment.

This sustainable means of binding textile reinforcing materials to rubber compounds has attracted substantial attention from within the industry since its developers first announced it as an open innovation technology in March 2019. More than 40 companies (tyre manufacturers, textile converters and suppliers) have expressed an interest in testing the material and are considering joining the licensing pool. Around 20 of these have already received samples. Now, all of the interested parties have been invited to join the pool and obtain free licensing in order to contribute to the development of this new green technology.

Sampling process exceeded expectations

“The sampling process was a big success and exceeded our expectations. Feedback from the industry encouraged us to proceed with the integration of Cokoon into our tyres and to begin series production of the first tyres back in 2019. Expanding use of the Cokoon technology in our tyre production in 2020 and in the following years is a high priority for us,” says Dr Andreas Topp, vice president Material and Process Development and Industrialization at Continental Tires.

This new technology enables the bonding activation of textile reinforcing materials with rubber compounds without the use of resorcinol and formaldehyde in the textile dip. Textile reinforcing materials are widely used in tyre manufacturing, as well as in the production of mechanical rubber goods such as hoses and conveyor belts.

Devrim Özaydin, global technology director at Kordsa, outlines the underlying idea: “With Cokoon, we want to implement an eco-friendly industry-wide standard for bonding textiles and rubber. We therefore invite all interested parties to join the pool, obtain free licensing, contribute to the enhancement of this new open technology and introduce Cokoon into their mass production.”

The licensing pool is handled by independent law firm AdvInno.