Jim Rowan recalls making PEEK tubes for Mobile (1993)

I was employed by Courtaulds Research in the Composites Research group and we worked in labs in 72 Lockhurst Lane.  Our manager was Charles Holleyman.  Our work was directly in support of Courtaulds Structural Composites, and was funded by Courtaulds Advanced Materials, so I reported to Charles and to Ed Trewin in CSC.  My role was in filament winding R&D, to develop materials and processes and make prototypes and one-off components.  

I helped manufacture, in Coventry, by filament winding, a tube of PEEK and glass fibre that was needed for the Alabama factory to make Tencel. We were told that the plant could not start up without this tube. I think it was to go in the flow line prior to the spinnerette and was part of a metal detector system. It had to be non-metallic yet very chemically resistant and strong. No other material could fulfil the requirements at the time, and almost nobody world-wide had the technology to make this unique structure. 

The job was something of an experiment as we had only done a limited amount of development to establish a process and some materials data because of the urgency to produce the tube.  All our previous years of R&D had been on carbon/PEEK, which processes differently from glass/PEEK, and we had never made anything remotely this big.  So it was a rather stressful 42 hour marathon requiring non-stop attention.  For example, we were winding a single 6 mm x 0.125 mm tape of glass/PEEK onto an irradiated rotating mandrel at about 300 degrees C and could not stop the process without overheating the product; the tape came on spools of limited length, so every few hours we had to weld the end of one tape onto the start of the next tape (using a soldering iron and paper clips) aided by a mechanism that accumulated enough tape to allow us just enough time to stop the spool while the winding continued. 

I have located the attached document which is a very brief summary, probably for someone like Jim Ratcliffe (who went on to greater things...)

Research Authorised and Development begins (1979)

On 4/10/79 a meeting took place in DF&VL "to decide whether to recommend that R&D work on alternative solvents for cellulose should be started".  Mike Welch (Head of DF&VL), Roger Lund (Deputy Head), Bill Brook (Head of Patent Dept), Jeff Branston, Fred Weymouth, Andy Hopkins, Dennis Woodward and Pat White were present.  If the answer was yes, then this group would decide the aims of the work and identify key areas to start.

At this meeting, the vulnerabilities of the viscose process versus a successful non-polluting solvent spinning development were listed as:

• Pollution and hazards.  Tightening environmental legislation would, if changes were made to comply, increase the costs of viscose by around 10p/kg in the USA, rather less in Europe.
• High spinning chemicals and recovery costs.
• High capital costs.  The US costs for an automated viscose plant using the latest technology would be 40% higher than a new polyester staple plant.

The combined chemical consumption, services and pollution control costs for any future viscose plant would be about 3x those of Courtaulds solvent spinning processes making acrylic and cellulose acetate fibres.

The wording of the conclusion was revealing: "if a recoverable solvent system could be found for cellulose it would be a serious threat" [to Courtaulds' viscose business]

Three potentially viable competitors for viscose were listed:

• The cuprammonium cellulose process where recent advances in ion-exchange solvent recovery had reduced energy costs and improved the viability of the technology.
• The ITT Rayonier DMF/N2O4 was too expensive by the published route due to solvent recovery difficulties.  However if Dupont's process for making anisotropic solutions with 30% cellulose content could be applied instead of ITT's 8% cellulose route, substantial reduction in costs would result.
• The AKZO amine-oxide process could be viable if a solvent recovery system could be developed, but it's costs were impossible to determine in the absence of any practical experience.  (Samples of amine-oxides had been made in the lab. and proved to be solvents for cellulose.)

The meeting agreed to undertake work on each of these systems to provide better information to decide future action:

• A range of amine-oxides would be made and screened and the most promising investigated in depth for solvent stability, potential hazards, recovery possibilities, spinning speeds, fibre properties, process costs, and capital costs.
• The solvating power of a range of known solvents would be investigated with the aim of finding anisotropic systems capable of yielding dopes with very high concentrations of cellulose.
• Because the cuprammonium system was showing no potential for growth, practical work would be avoided but contacts with the producers would be made to ascertain current pros and cons.

This work would be carried out by 2 graduates and would be reviewed after 6 months.

Lenzing report record sales now the new Tencel plant is on line (2014)

Lenzing reported very high production volumes in the first three quarters of 2014, operating all its fiber production facilities at full capacity. A new record sales volume of 706,900 tons was achieved (Q1-3 2013: approx. 660,000 tons). This is all the more remarkable given the fact that all industrial plants in the greater Nanjing area of China, including Lenzing, were forced to reduce production due to the Nanjing 2014 Youth Olympic Games.

The new sales record is mainly attributable to the successful ramp-up of the new TENCEL® fiber production facility at the Lenzing site in Upper Austria towards the middle of 2014. Sales of the Segment Fibers in the first three quarters of 2014 totaled EUR 1,285.4 mn, comprising a drop of 3.1% from EUR 1,326.5 mn generated in the first three quarters of 2013. Segment EBITDA in the first nine months of 2014 amounted to EUR 155.1 mn, 15.8% lower than EUR 184.1 mn in the previous year, whereas segment EBIT of EUR 64.6 mn comprised a 35.5% decline from the prior-year figure of EUR 100.1 mn. 

Specialty fibers accounted for about 39% of total sales revenue in the Segment Fibers.  Lenzing continued to generate very attractive price premiums for the specialty fiber Lenzing Modal® in contrast to viscose fibers, against the backdrop of ongoing high demand. The price premiums achieved for TENCEL® fibers remain at a very attractive level, although prices for new samples and market development projects declined somewhat in individual cases. 

The focus of Lenzing’s marketing activities in the third quarter was on further developing the market for TENCEL® fibers. The market penetration efforts to promote the use of Lenzing fibers in denim have met with success, as demonstrated by the fact that the most prominent jeans manufacturers are integrating TENCEL® fibers in their fashion collections. Demand for TENCEL® bed linen remained strong, especially on overseas markets. In the home textiles segment, Lenzing promoted the use of TENCEL® fibers in towels, opening up new application possibilities with large American retail chain stores. 

A new study in the nonwovens segment confirms that TENCEL® BIOSOFT fibers

significantly enhance wearing comfort when used as a top sheet for incontinence pads.

This extract from the Lenzing quarterly report confirms the successful start of the 67,000 tonne/year Tencel plant in Austria. (A producer-blend of Tencel and cotton is apparently taking the bulk of the new Tencel production and allowing cheaper cottons to be upgraded.  Such a blend was part of the strategy for moving the sudden surplus of Tencel when the Courtaulds Mobile plant started in 1992.  It's also nice to hear the fashion for Tencel in denim - the original launch market - is returning.)

Source: Lenzing Interim Report - 01/09/2014

First reports on solvent spinning (1976-77)

In the mid-seventies the rising influence of the US anti-pollution lobby motivated several US cellulose research groups to renew efforts to find alternatives to the xanthate dissolution route.  Chief among these was ITT Rayonier and it was their publications which stimulated a review of the new possibilities.  This was done in Courtaulds Development Fibres and Viscose Laboratory (DFVL) - the new name for what had been the Viscose Research Laboratory (VRL) in Coventry.

Brian Gardner's August 1976 File Note entitled "Solvents for Cellulose and their Application to Film and Fibre Production - A Literature and Patent Survey." reviewed the available routes but made no attempt to evaluate their suitability as a commercial alternative to xanthation.

Mike Summers-Smith extended Brian's survey in early 1977 and added conclusions on how useful these processes might be.  He listed the disadvantages of the viscose route as identified by ITT Rayonier as:

• High levels of air and water pollution.  Viscose uses strong acids, alkalis, CS2 and its regeneration liberates H2S.  (Mike noted that none of these pollutants need be emitted from the plant and all chemicals could be efficiently recycled given a high enough capital expenditure and energy outlay.  However this would render the fibres uneconomic compared with cotton and the new synthetics.)
• High capital costs.  The lengthy process with critical ageing times for alk-cell and viscose, coupled with dilute polymer solutions and slow wet-spinning processes made viscose plants fundamentally expensive.
• High energy consumption.  Major advances in energy conservation were unlikely.
• High labour costs.  (However the new automated viscose plants with slurry steeping, belt mercerising, wet-xanthation, backwash filters and continuous deaeration were bringing this under control).
• Increasing raw material costs, but these could be limited by increased recovery.

The new processes were divided into 4 classes according to the chemistry involved i.e. cellulose behaving as a complex or as a derivative, as a base, or as an acid.

Lenzing starts world’s largest Lycoell fibre plant (2014)

This appeared on the Fibre2Fashion website and Courtaulds gets a rare mention. It will be interesting to learn where the 67,000 tonnes of Tencel from the new line said to be "running at full capacity" is being sold.

September 19, 2014 (Austria)


Within 24 months of starting construction, Austria based Lenzing AG has started commercial production at the world’s largest production facility for Lyocell fibers.

The plant which is now running at full capacity was set up at an investment of € 150 million and will produce Tencel fibre.

Lenzing said the setting up of the Tencel production plant in Austria went according to plan, both financially and in terms of time.

This new factory in Lenzing is the first in the industry to feature a single production line with an annual nominal capacity of 67,000 tons.

The new plant design incorporates lessons learnt with experience from three existing Lenzing Group Tencel production plants in Austria, USA and UK.

As a result, the new Tencel plant in Lenzing represents the world’s leading generation of Tencel technology, Lenzing explained.

Lenzing said with Tencel, it offers the industry a fiber material for the future and in terms of ecology and innovative strength, the fiber represents a milestone.

The fiber producer said, “A plethora of textile applications has been derived from the new generation of fibers from activewear to denim and shirting in which Tencel has proven its strength.”

“Until now woven products made from Tencel were promoted. However, new Tencel fibers for knitwear applications lead us to perceive tremendous potential in the fashion knitwear segment”, Robert Kerkhof, CCO at Lenzing said.

“Thanks to its bright colors and more attractive appearance, Tencel will set a new standard in this sector too,” he added.

The search for a cellulose fiber with an ecological and economic production process led researchers to Lyocell.

Lenzing and the former fiber producers, Courtaulds, nurtured Lyocell to market maturity as a result of intensive research work and their strong belief in the new fiber of the future.

The first production facility was started in 1992 and in 2004 Lenzing was able to pool all of its resources as a result of buying the Tencel brand and capitalize on this expertise in fiber production.

As a result of purchasing the Tencel brand name, Lenzing was able to market the entire Lyocell business under this well known fiber name. (AR)

Source: http://www.fibre2fashion.com/