The Textile Effects division of US-based Huntsman Corporation has sued Zhejiang Longsheng Group Co Ltd and subsidiaries Zhejiang Keyong Chemical Co Ltd and Shanghai Colva Dyestuff Co Ltd for infringing its Chinese patent by making and selling certain black dyes.

Huntsman is seeking substantial damages of 231 million yuan and an injunction against further infringement. After Huntsman filed suit with the Shanghai High People's Court, Longsheng, Keyong and Colva each submitted jurisdictional objections, which were subsequently rejected. The case is still ongoing.

Huntsman's lawsuit follows the decision of the Shanghai High People's Court affirming the judgment of the Shanghai First Intermediate People's Court in May 2013, which found that Colva had infringed Huntsman's Chinese Patent No ZL00106403.7 by manufacturing and selling Colvazol Super Black LC-G and Colvazol Super Black LC-R. Colva was ordered to immediately stop manufacturing and selling the infringing products and pay statutory damages to Huntsman.

Longsheng controls both Keyong and Colva, and all three companies manufacture and sell textile dyes in China. Longsheng also has majority ownership of the Dystar Group.

Paul Hulme, president of Huntsman Textile Effects, said: "Huntsman is committed to protecting its intellectual property rights, and will vigorously pursue those who are making and selling infringing products and to obtain full compensation for our damages".