German polymer materials manufacturer, Covestro, textile technology company Huafeng and green fiber technology company Cyclone from China, have collaborated to develop a solution for producing high-quality running and sports shoes in a far more sustainable way than before.

Recycled fabric made from CYCLONE® recycled polyester (rPET) yarns is used as the shoe upper and selectively coated using Huafeng's HAPTIC® technology. Huafeng employs a polyurethane (PU) dispersion from Covestro's INSQIN® portfolio, with half of its carbon content derived from bio-based raw materials. Each pair of shoes made in this manner emits roughly 230 grams of CO2 equivalent less than a pair made with traditional fossil-based PU dispersions and virgin PET fabric.

Tony Wu, Global Marketing Manager, Textile Coatings, Covestro, said that this is wonderful news for everyone who wishes to live an athletically active, healthy lifestyle in the most ecologically friendly way possible. He underlines that the improved sustainability does not impact the footwear upper's durability, look, or comfort. 3D shapes can be applied to textile materials using Huafeng HAPTIC® printing technology, resulting in trendy designs and outstanding performance in athletic footwear.

The INSQIN® series of aqueous textile coating resins include Impranil® eco DLS, a largely bio-based binder. Its use leads to lower greenhouse gas emissions with roughly 60 grams of CO2 equivalents each pair of shoes. Internal computations have been confirmed by independent external specialists.

It is evident that the difference in the CO2 footprint becomes significantly bigger when solvent-based PU textile coatings are utilized for comparison. The use of fabric made from recycled PET yarns reduces greenhouse gas emissions by approximately 170 grams for every pair of shoes.

Covestro, Huafeng, and Cyclone collaborated to host a global webinar to introduce the three technologies and the synergy formed by this co-development. 

Dr. Thomas Schmidt, Director of Innovation said that at Huafeng, they believe that sustainability is critical to our market success. They were able to add more renewable materials into their HAPTIC® coatings with the support of Covestro's largely bio-based PU dispersion, significantly boosting their sustainability.

Dr. Torsten Pohl, Head of Global Textile Coatings at Covestro, adds that the combination of their largely bio-based INSQIN® PU coating binder with Huafeng HAPTIC® printing on recycled PET fabric shows how partners in the value chain can work together to create more sustainable products.