Courtaulds/Lenzing in Lyocell fibre patent dispute (1994)

25 July 1994 [Source: ICB]

A PATENT dispute between rival fibre manufacturers Courtaulds of the UK and Lenzing of Austria casts a cloud over commercialisation of the new generation of cellulosic fibre materials. Lenzing, which last month revealed plans to scale up its Lyocell fibre (ECN 4 July), has instigated legal proceedings in the US against Courtaulds, which has been producing its Tencel fibre at a commercial-scale plant in Alabama since 1992.

Lenzing, which has been granted both a US and a European patent on one aspect of the solvent-spun (cellulose in amine oxide) manufacturing process, is alleging infringement of its US patent by Courtaulds. Courtaulds argues that both patents are invalid in that they relate to an item of equipment that has been in the public domain since the 1970s.

Courtaulds is seeking to have Lenzing's action in a New York court dismissed by summary judgement and to have the patent declared invalid. In Europe, a second higher instance decision on Lenzing's European patent is expected later this year. A first instance decision was awarded in Lenzing's favour this May, despite opposition from Courtaulds and Akzo. A Courtaulds spokeswoman said the company was confident that Lenzing's European patent will in due course be declared invalid and that the company has strong defences to any claim for infringement.

Courtaulds has filed 44 patents of its own relating to Tencel, the

spokeswoman added. Amongst those allowed to date, a number are critical to the solvent-spun cellulosic process, she claimed. 'These would preclude Lenzing or any other company from using the process without Courtaulds' consent.'

Courtaulds opened its 18 000 tonne/year unit in Mobile, Alabama, in 1992. A second unit at the same site is now under construction, set to raise capacity to 43 000 tonne/year by mid-1995. In May, the company confirmed plans for a European unit to bring total capacity to 70 000 tonne/year by 1996. A fourth plant in Asia is also proposed.

In a briefing to analysts last week, Courtaulds was bullish about prospects for Tencel. The company said preliminary figures indicated that Tencel would represent some $60m in turnover for the year 1993-94 and revealed a strategic vision of achieving a $500m turnover in the fibre by the year 2000.

Meanwhile, Lenzing is 'more than satisfied' with initial market feedback on its Lyocell product, currently being produced on a 500 tonne/year pilot unit at Lenzing. Ingo Marini, director of Lenzing Lyocell, claims the Lenzing process offers a better degree of control of the fibrillation, so preparing Lyocell for a broader range of applications than Tencel. Financing activities for a commercial-scale Lyocell project have begun, with a capacity of 20 000 tonne/year planned to be running by the end of 1996, Marini told ECN. Following Austria's recent decision to join the EU, a new site outside Austria is believed to be the preferred location. Akzo is conducting research for the production of a cellulosic continuous filament yarn, Newcell. A pilot plant to make yarns for fine, silk-like fabrics has been commissioned at Obernburg, near Frankfurt.