Tuesday, July 31, 2012

Tencel debuts as Genesis (1986)

The first public announcement of the Genesis project was in the June 7th 1986 issue of Nonwoven Markets Newsletter, the leading US nonwoven news source at that time.  This has been kindly scanned and sent in by David Allan, Editor, yesterday.  The original was apparently rather yellow and the text has been doubled in size to improve its readability. (Hopefully a better copy will emerge.)

Points to note:
  • Amine oxide is described as a "light duty detergent".
  • Courtaulds say marketing is using a "Scattergun approach"
  • The fibre will target mid to high end cotton apparel, sheeting in home textiles and speciality wipes in nonwovens.
  • 50kg batches of fibre are being made.
  • A larger Coventry pilot line is under construction and due to start in early 1987.
  • Future expansion in the USA "as soon as commercially feasible"
A copy of the original follows.  It was written by the then editor, Lydia Cain, who enjoyed a visit to Courtaulds Research and a Stratford on Avon river cruise (along with several European journalists whose articles have yet to re-appear) at the invitation of Viscose Europe.  Pat White and I gave the presentations on Genesis and nonwovens development respectively.

Click to enlarge: clockwise from Lydia Cain in the port bow: me, Peter Lennox-Kerr, Pat White, ?, ?,Geoff Blackburn, To the left of Lydia, Robin Anson. No others recognisable.

Below is a photo from Courtaulds News sent in by Iain Jack.  On this one Siggy Waegner is standing behind Pat White

Monday, July 30, 2012

Hydroentanglement of Tencel (1989)

The abstract below makes it look as if Duncan Rhodes and I collaborated on an article but there were two separate articles here, one on cotton and one on rayon.  Later Duncan (Technical Manager at Edward Hall - cotton bleachers) and I did collaborate on a study of cotton/Tencel blends in hydroentanglement but this has yet to appear in the abstracts.  I can also recall putting a tonne of Tencel through the Edward Hall kiers a few years after this in order to degrade it to make a faster fibrillating fibre.  (The optimisation of the Tencel process for textiles had stopped the easy fibrillation which was so attractive in the first HE nonwovens - circa 1986)  

This Chapter presents articles on the main raw materials used in the manufacture of spunlace products. A study of the importance of cotton in the textiles industry worldwide as well as its suitability for nonwovens is contained in 'Cotton: the natural fibre in nonwovens' (Rhodes D). This article examines the use of cotton in nonwovens and considers properties of nonwovens containing cotton which may be achieved for various applications. The benefits of combining spunlace technology and rayon fibres are outlined in 'Rayon used in spunlacing' (Woodings C R), which also describes the Tencel solvent spun cellulose process.

Rhodes D; Woodings C R, Spunlace Technology Today, edited by Vargas E, Chapter VI, pp 50-68, [San Francisco, CA, USA: Miller Freeman Publications, 1989, 146pp]

Hydroentanglement of Tencel (1986)

This is the earliest set of results to emerge so far on Genesis in hydroentanglement.  It is from the Sept 1986 "Project Genesis" document and shows the remarkable wet fabric properties obtained on a production line in Chicopee Cuijk and on Courtaulds Research Honeycomb* pilot line. 

*Honeycomb were, before Perfojet started offering machinery a year or two after this, the only supplier for this process.  They had supplied part of the Dupont Sontara hydroentanglement process.  Dupont and Chicopee were the only practitioners of the technology (high pressure water jets entangling a loose web of fibre on a perforated conveyor).  In Japan, Unicharm had developed a low pressure system with no conveyor thus avoiding the Dupont/Chicopee patents.  Courtaulds bought this system and were installing a production line at their BFF nonwoven plant in Bridgwater at this time.

Saturday, July 28, 2012

The Wykes-Quigley Patent (1993)

After  10 years of "silence" the patents on the Tencel process begin to emerge.  

United States Patent
Wykes ,   et al.October 11, 1994

Transport of solutions of cellulose through pipes

A method for transporting a solution of cellulose in aqueous N-methylmorpholine N-oxide through a pipe, the temperature in degrees centigrade of said solution in the center of said pipe being controlled at 1000/(X+0.98 x.sqroot.D) and/or the temperature of said solution at the interior wall of said pipe being controlled at 1000/(Y+1.15 x.sqroot.D) where D represents the internal diameter of the pipe in inches, X represents a value equal to or greater than 5.0, and Y represents a value equal to or greater than 5.4.

Inventors:Wykes; Katharine A. (Wellesbourne, GB), Quigley; Michael C. (Meriden, GB)
Assignee:Courtaulds Fibres (Holdings) Limited (London, GB2
Appl. No.:08/069,184
Filed:May 28, 1993

Click Here for the Full Patent

Lenzing introduce Lyocell (1991)

Here's the first paper I could find referring to Lenzing's development of the solvent spun cellulose process.  This paper doesn't appear in Lenzinger Berichte: the first mention of lyocell in this Journal appears in 1994.

The new cellulose fibre Lyocell has been developed by Lenzing AG as an attempt to solve problems expected in the future with raw material supplies due to a growing world population and increasing fibre consumption as well as to provide a new generation of fibre. Taking into account the strengths and weaknesses of existing fibres like synthetics, cotton and viscose, the merits and disadvantages of the new generation of Lyocell fibre are discussed. Fabric structures produced from Lyocell possess high tear resistance, uniformity, wear comfort and shrink very little during washing or lamination. Fibrillation presents a problem. Other advantages include biological degradability and an inexhaustible raw material resource.

Firgo H, International Man-Made Fibres Congress, 12-14 June 1991, at Dornbirn, Austria

Thursday, July 26, 2012


As the most abundantly available organic raw material in the world, new uses are constantly being found for cellulose. The viscose-rayon process is still widely used, but there have always been attempts to devise an alternative, preferably based on a solvent which dissolves the cellulose directly and can be easily recovered after spinning. The Newcell, DMAc/LiCl and Celca processes have all proved to yield more brittle fibres than the viscose-rayon method. The production of high tenacity, high modulus cellulose yarns by spinning anisotropic cellulose triacetate solutions followed by saponification to cellulose yarn is not a true alternative, since the yarn has much higher strength and modulus and lower elongation than conventional rayon. The super-cellulose yarns as yet produced are not suitable for commercial production.

Vollbracht L., Chemiefasern Text. Ind., Man-Made Fiber Year Book 1989, pp 32, 35-36

Wednesday, July 25, 2012

Conclusions from Nonwoven Developments with Tencel (1989)

These were the conclusions from work on Tencel in nonwovens between mid 1987 and end 1989.  They were presented at EDANA's INDEX 90 Congress in Geneva.  Tencel's performance in wet-laid hydroentanglement was particularly striking, because properties comparable to dry-laid were achievable in this potentially higher productivity process.

The environmental aspects of solvent-spun cellulose production and use (1991)

Life on this planet can be said to depend on the carbon cycle in general and the processes of respiration and photosynthesis in particular. Animal respiration converts oxygen to carbon dioxide in the process of extracting energy from carbon compounds created by green plants. Green plants in their turn convert carbon dioxide into oxygen needed by animals, and in the process make the carbon compounds (mainly cellulose) required to enable both the plants and the animals to grow.

It is no accident that a balance has evolved between the plant and animal kingdoms over a few billion years of evolution. In the last 200 years however, industrialisation and the accompanying rapid growth of population, fossil fuel burning and of deforestation, have begun to affect this balance. Our survival as a species could be at stake, and as this becomes increasingly clear to the public at large, the pressures to modify "Industry" to increase our chances of survival will be enormous.
A key issue is overpopulation. The human race has proved so successful that the industrial system needed to sustain its growth is upsetting the natural cycle from which Homo sapiens evolved. If we reverse industrialisation - we would need to turn the clock back by about 200 years - the resulting human misery in terms of the lack of the basic necessities of life would be incalculable. The shortages of food, water, warmth, shelter and clothing would lead to global living standards falling to levels which would be intolerable in any country. This would certainly result in reduced population, but is clearly an unacceptable way forward, and unlikely ever to be allowed to occur. We are equally unlikely to be able to persuade families to have only one child. So, it looks as if we are stuck with a large and growing population, and must therefore turn to science to help us move towards a balanced environment maintained by a sustainable industrial system.
The fibre industry, defined in cradle-grave terms to include such sectors as polymer making, textiles and nonwovens, and their disposal methods, provide some of the basic necessities of 20th century life. Our responsibility is to try and minimise the environmental impact of the processes by which such products are manufactured.
To do this we need to make comparisons, using the best available science, of the environmental impacts of the routes to fibrous products. We must also remember that all products made form our fibres will ultimately require disposal, and that it is our duty to ensure that the disposal methods available are environmentally sound.
Such cradle-to-grave comparisons are of course complex, difficult to carry out, and beyond the scope of this paper. Here we indicate some of the environmental factors which come into play when investing in a new fibre which could become one of the major raw materials for the textiles industry in the coming decades.


Our new fibre making process has one major raw material, the cellulose polymer, and one minor raw material, the amine oxide solvent. It also requires energy. If markets evolve along traditional lines, then some versions of the fibre will contain titanium dioxide dulling agents, and some will be bleached. All are likely to be finished with the surfactants needed by the subsequent conversion processes. Perhaps we should stress that the non- cellulosic components and bleaching options arise because the market demands them, not because they are an essential part of our process.


Cellulose is the natural polymer which makes up the living cells of all vegetation. It is the material at the centre of the carbon cycle, and the most abundant and renewable biopolymer on the planet. Rayon fibre producers have converted it from the fine short fibres which come from trees into the fine long fibres used by textiles and nonwovens for almost a century. Rayon nevertheless remains unique among the mass produced man-made fibres because it is the only one to use the natural polymer directly.
Polyesters, nylons, polyolefins, and acrylics all come indirectly from vegetation. They come from the polymerisation of monomers obtained from fossil fuels, which in turn are formed by the incomplete biodegradation of vegetation which grew millions of years ago.
Cellulose is produced in the cell walls of vegetation when sugars are polymerised by enzymes to form both lignin and cellulose. The sugars are produced from carbon dioxide and water by the action of sunlight on the green catalyst chlorophyll in the leaves of the plants. The industrial grade of cellulose used to make our rayon comes from tree-farms, where specially chosen species are grown from sapling to maturity in 7-10 years. New trees grow from the stumps of the cut trees, and this happens on marginal land, generally unsuitable for food crops and without the intensive use of fertilisers or pesticides. The best farms yield in excess of 2.5 tonnes of pure cellulose per acre per year. For comparison, cotton growing at its most intensive yields about 0.35 tonnes/acre and needs good soil.
Cutting down trees is popularly regarded as an unfriendly activity, and it is therefore quite important to put the usage of trees as a raw material in the correct perspective. It has been estimated (1,2) that:

  • 100 billion tonnes of vegetation grow and decay annually on land. This represents about 12% of the planets total production of vegetation, the majority being produced in the oceans.
  • 12% of this land-based vegetation is in the form of wood (trees).
  • Of this 12 billion tonnes of wood, a maximum of 3 billion tonnes is removed by man. Half of this is burnt, either as fuel or to clear land for agriculture. The other half is used by Industry. (Compare this with 6 billion tonnes of fossil reserves "mined" each year.)
  • Of the 1.5 billion tonnes of wood used by industry, half becomes timber in saw mills, and half is used raw.
  • Of the 0.75 billion tonnes used raw, half goes into construction (pit-props, telegraph poles etc) and half is converted into pulp and chipboard.
  • Of this 0.375 billion tonnes, 0.29 billion tonnes of wood become wood-pulp for the paper, board, fibre, film and chemicals industry.
  • A significant proportion of this 290,000,000 tonnes of pulpmill feedstock (up to 40% in some areas) comes from forest thinnings, and saw mill waste and 6% from non-pulp sources such as straw, bagasse, hemp and cotton. This feedstock yields 161,000,000 tonnes of pulp.
  • About 4.5 million tonnes of this pulp output are a high quality dissolving grade for forming into fibres, films, water soluble polymers and chemicals. Dissolving grade pulp is perhaps better described as industrial grade cellulose polymer, and should be considered alongside the polyester or nylon polymer beads which are the feedstocks of the synthetic fibre plants.
  • Viscose rayon manufacture consumes 2,600,000 tonnes of this cellulose, with 2 million tonnes going into the staple fibre process.
Our Mobile rayon plant currently uses about 100,000 tonnes/year of the industrial grade cellulose to make viscose rayon fibres. When the first Tencel plant is on stream, an additional 18,000 tonnes/year will be required.

Cellulose Extraction (Pulping)

From the above figures, it can be seen that the 2.6 million tonnes of dissolving grade pulp currently manufactured to feed the rayon fibre industry represents 0.01% of the annual production of cellulose, on land, in nature, and about 0.7% of the cellulose in wood used by industry.
The Tencel process as currently designed will use the same sources of pulp (at slightly higher levels of efficiency) as the viscose process, but concerns related to pulp mill effluents are still with us. However I think we can by now conclude that concerns over dioxins in the pulp itself, and products made from the pulp are now behind us. Our raw material and final products, both viscose and solvent-process, have been shown by independent analysis to be free of such compounds at a detection level of 0.5 parts per trillion.
With regard to the pulp mill effluent issue, our major suppliers are undertaking programmes of work to eliminate elemental chlorine at the pulp bleaching stage, and these changes should be complete before the new fibre becomes commercial in the second half of 1992. Alternative pulping sequences which eliminate all chlorine compounds from the process are being investigated for use in both viscose and solvent systems.

Amine Oxide Solvent

N-methylmorpholine N-oxide (NMMO) is the solvent used. It is manufactured by methylation and oxidation of morpholine, which comes from a reaction between diethylene glycol and ammonia.
Whilst this is the only major chemical used in the Tencel process, its consumption is reduced to the absolute minimum by the recycling which is made possible by solvent recovery. In our Grimsby plant, which has been operating semi-commercially for the last 3 years, we have developed techniques which now recycle virtually all of the solvent used to dissolve the pulp.
Strong NMMO solution as delivered to our process has been subjected to a series of acute mammalian toxicological evaluations with conclusions as follows:
Oral LD50:
"This material is considered to be practically non-toxic by the oral route and would not be considered harmful by EEC labelling criteria."
Dermal LD50:
"This material is considered practically non-toxic by the dermal route, and would not be considered harmful by EEC labelling criteria."
Dermal Irritation:
"This material is considered to be minimally irritating to the skin, and would not be considered a skin irritant by EEC criteria."
Ocular Irritation:
"This material is considered to be minimally irritating to the eye, and would not be considered an eye irritant by EEC criteria."
In-vitro genotoxicity studies were also carried out on dilute solutions of the NMMO solvent. The test samples were inactive in Cell transformation, Mouse lymphoma forward mutation, Primary rat hepatocyte/DNA repair, and Optimised Ames assays.
In short, our solvent is harmless over the range of concentrations used in the plant, and especially so in the minimal concentrations likely to occur in any effluent.


The usage of energy and the means by which it is obtained contributes a major component of the environmental impact of most complex industrial process sequences.
The methodology of assessing the energy usage of products and processes is currently the subject of much debate, and a standardised approach has yet to emerge. Not surprisingly, most of the published work on fibres was carried out during the last energy crises in the 1973-81 period, and we could find nothing in the public domain from more recent studies.
We are aware of the following attempts (refs 3-7) to assess the total energy required to make baled staple fibre from naturally occuring raw materials, wood in the case of cellulosics and oil in the case of synthetics. In general they break the fibre production sequence into monomer making, polymer making and fibre production, and while a variety of fibres are covered, only viscose rayon and polyester are mentioned in all of them. Tonnes of fuel oil equivalent per tonne of fibre were the most popular units (TFOE/T), and Table 1 gives the values.

Table 1

Woodhead 3
Lane and McCombes 4
Kogler 5
Armstrong 6
100 (base 100)
Marini and Six 7
100 (base 100)

In the same papers, nylon and acrylic fibres, where shown, require more energy than polyester (about 5 times the rayon value), and polypropylene requires less, (About 1.7 times the rayon value). Cotton requires less energy than viscose up to the bales of raw fibre, but data for the bleached and cleaned version generally needed in nonwovens is not presented.
The overall picture that emerges from these early studies was that whilst the wet-spun cellulosic fibres required more energy than melt spun polyester for the fibre making step, they had no monomer energy requirement, and the "polymerisation" requirement was minimal. In the case of the very low values for rayon emerging from Lenzing and CIRFS, we think full credit was being given for the fact that the pulp mills energy needs were in fact renewable and not dependent on fossil fuels, and that pulp could be fed directly into the viscose process without incurring any transport or drying cost. In other words, the pulp mill could be driven entirely by energy obtained from burning the parts of the tree which were not needed in the final product, and this "free" and renewable energy was not counted.
From an energy viewpoint, the solvent route to cellulosic fibres is identical to the viscose route up to the point where the cellulose enters the solvent. The energy requirements for the non-cellulosic raw materials is significantly lower in the case of the solvent route, but the solvent route will require similar energy levels in dope handling, spinning, washing and recycling. The lower water imbibition of the solvent fibre (65% versus 95%) will yield savings in fibre drying and of course in any subsequent washing and drying operations.
Overall, the solvent route will show a useful economy in this important resource when compared with viscose production on the same scale.

Fossil Reserves

Renewable resources will become increasingly important as the planets stocks of fossilised reserves are depleted and as governments realise that biomass can provide a truly sustainable, cost-effective source of energy and materials.
The viscose route currently needs fossil reserves for energy generation but for little else. At our Mobile plant the vast majority of energy requirements come from locally available natural gas.
The solvent used in the new process is made from ethylene glycol which currently comes via ethylene from oil refineries. However, as indicated above, the recycling rate is so high that solvent usage is kept down to a few kilos per tonne of fibre, and hence fossil reserve dependence is minimal.

Gaseous Effluents

The Tencel process involves direct dissolution of cellulose in a liquid which is recycled very efficiently. There are no chemical reactions and no by-products of the sort which are unavoidable in the regeneration of cellulose from the viscose route.
In the viscose process, gaseous effluent control and treatment is a fundamentally important part of the overall process and is continuously improving as the technology of the "closed-box" process evolves. The air handling and cleaning systems employed are costly and most of the emissions to atmosphere are collected and discharged through tall stacks.

The Tencel process produces very little atmospheric emission. There are traces of volatile organic compounds associated with the solvent and the soft finish which will leave the plant in the normal course of ventilation. There is no need for any central air handling or emissions stack.

Liquid Effluents

The spinning and washing liquors from the viscose process are recycled to allow reuse of the sulphuric acid and zinc sulphate components wherever this is feasible from economic and environmental standpoints. Nevertheless, in common with most industrial washing and bleaching systems, large volumes of process water have to be cleaned on-site before discharge to river. As is the case with gaseous effluents, most rayon producers stay well ahead of the regulatory requirements and this means continuously working towards improved plant designs.
The Tencel route uses much less water overall, and the process effluent needs significantly less treatment.


Cellulosic fibres are, as we stated at the start of this paper, simply a tiny subset of the most abundant bio-polymer on the planet.
Like natural vegetation, they can become food for micro-organisms and higher life forms (they biodegrade) and they will burn with a rather greater yield of energy than natural vegetation.
In complete biodegradation or incineration, the final breakdown products are carbon dioxide and water, and so in the overall sense these disposal methods simply recycle the cellulose to the atmospheric components from which it was made.
It is also possible to liberate and use some of the "free" solar energy which powered the polymerisation step. In the case of incineration this is straightforward in that the free-burning cellulose can be used to generate steam etc. In the case of landfill disposal, it is now well known that slow anaerobic biodegradation occurs in all landfill sites dealing with municipal solid waste. This process generates methane from cellulose, which can, and increasingly is, being used to drive gas-turbines directly. Admittedly, this process makes only a small contribution to reducing the volume of waste in the landfill, but as fuel costs rise, this "free" and renewable energy source will become more important. If landfills are designed from the start to be anaerobic bioreactors, i.e. lined and operated with moisture addition and leachate recycling, then energy generation and the return of land to normal use can be accelerated. 9
Our tests show that the anaerobic degradation process is so fast that disposables made from cellulosic fibres are likely to disappear, yielding their energy content, in the sludge digestion process used in sewage farms. I think we could all agree, that, given good mains sewage systems, and disposable designed to avoid toilet blockage, all soiled sanitary products would be better disposed of by flushing. It is only the current need for some non-cellulosic components which prevents this ideal being attained.


This paper discussed some of the environmental issues which have to be considered when developing new production plant for textile and nonwovens raw materials.
Rayon fibres, made for a century by the direct conversion of abundant vegetable matter, have always had much to recommend them in textiles compared with synthetics made from fossil fuels. The renewability of their main raw material, their overall energy efficiency, their lack of dependence on fossil fuels, their long history of safe use in hygiene applications, and their easy disposal and natural recyclability make them strong contenders for tomorrow's textile industry also.
The new Tencel route to rayon reinforces these inherent strengths by using a modern fibre production system which, being physical rather than chemical, reduces environmental impacts to a minimum. The Tencel investment, coupled with the continuous improvement of the traditional route, gives us what we believe is a winning approach to textile industry fibre supply for some time to come. The new plant is due to be on-stream at Mobile Alabama in mid 1992.


1 "Eco-profiling of cellulose-based products", August 1990. (A study prepared for Courtaulds and others by Envirocell - 256 references).
2 John Emsley (Kings College London) - "Plant a tree for Chemistry", published in New Scientist, 8th October 1987.
3 Woodhead; ICI; International TNO Conference; 1976.
4 Lane and McCombes; Courtaulds; Textile Manufacturer No 1; 1979.
5 Kogler; Lenzing; EDANA AGM; Munich 1980.
6 Armstrong; Consultant; EDANA AGM; Munich 1980.
7 Marini and Six; EDANA Nonwovens Symposium Milan, 1985.
8 Unpublished Data; Interantional Committee for Rayon and Synthetic Fibres; 1982
9 Pohland and Cross, "Controlled Landfill Management - Principles and Applications"; Insight 91, Charleston, Oct 91.

Calvin Woodings
Research Fellow
Courtaulds Research, Coventry

Monday, July 23, 2012

Genesis in Textiles. The 1986 View (2)

Fibrillation and dyeing were not thought to be problems for woven fabrics at this time.

(This extract is from a document entitled "Project Genesis" 1/9/86, but no authors are mentioned)

Tencel News: Lenzing AG Intensifies Pulp Cooperation with Sappi (2012)

Lenzing AG, global market leader for man-made cellulose fibers, is intensifying its longstanding cooperation with the paper and pulp group Sappi. Both companies have concluded a multi-year pulp delivery contract at comparable terms and conditions with pricing linked to paper pulp as in the existing supply contract. The agreement is related to the construction of new dissolving pulp capacities by Sappi.

Sappi is the world’s largest manufacturer of dissolving pulp with an annual capacity of 800,000 tons at present growing to 1.3 million tons. Dissolving pulp is used in producing cellulose fibers, amongst other purposes. The raw material is wood mainly derived from certified eucalyptus plantations. Lenzing has already been sourcing high quality pulp for its non-integrated fiber production plants in Indonesia, China, Europe and the USA for several decades, including from the Sappi Group.

For more information please contact:
Angelika Guldt
Head of Corporate Communications
Phone: +43 (0) 7672 701-2713
E-mail: a.guldt@lenzing.com

Saturday, July 21, 2012


Austrian company Lenzing AG has announced the acceptance of the name Lyocell by BISFA as the generic name for solvent-spun viscose rayon. A solvent-spun rayon from Courtaulds Fibers Inc. called Tencel is reported to show similar characteristics, i.e. high strength and the tendency to fibrillate under certain conditions. As all the solvent employed in the solvent-spun rayon process is reclaimed and recycled and no unpleasant effluent is emitted, the new Lenzing technology is justifiably labelled as environmentally friendly.   

Anon., Nonwovens Mark., vol. 6, no. 14, 12 July 1991, p. 8

Friday, July 20, 2012

Genesis in Textiles: The 1986 View (1)

This piece considers yarn manufacture, the next to be posted will cover knitting and weaving.  Interesting to see ENKA "Newcell" mentioned as being good on the Murata system. Was this before they decided to focus on continuous filament yarns or were they feeding "Newcell" filament as a core for other staples?

(This extract is from a document entitled "Project Genesis" 1/9/86, but no authors are mentioned)

Thursday, July 19, 2012


Courtaulds Research, the research division of Courtaulds plc, UK, unveiled a programme called Focus Nonwovens at the Textile and Technology Exhibition in Manchester in February 1990. This offers the services of Courtauld's personnel to companies involved in nonwovens. The team has already been involved in extensive consultancy work with the Courtaulds family of businesses such as: Courtaulds Viscose, Tencel, Courtelle, Performance Products and Acetate. 

A range of pilot scale nonwovens development equipment is available for use by clients, to manufacture dry and wet-laid webs, followed by bonding using either heat, latex, hydroentanglement or needling. A Neue Bruderhaus wet lay machine, a Honeycomb hydroentangler and a latex bonding unit are arranged in-line.

Haddad C, Nonwovens Ind. vol. 21, no. 4, Apr. 1990, p. 50

Wednesday, July 18, 2012


Courtaulds plc plans to build the first production plant for Tencel solvent spun cellulosic staple fibre at its rayon manufacturing facilities near Mobile, Alabama, USA. Startup is scheduled for summer 1992. Initial capacity will be 40m lb per year. The process uses amine oxide as a dissolving agent and has been demonstrated for two years at a pilot plant in Grimsby, UK. It is said to offer an environmentally secure process. Tencel has been evaluated on nonwoven hydroentanglement systems.

Anon, Nonwovens Mark.vol. 5, no. 12, 8 June 1990, pp 1-2


Possible routes to high performance cellulose are described, and discussed in a qualitative way. Recent findings and developments in the field of high modulus fibres are considered in terms of their applicability to cellulose. In particular, reference is made to production methods for high strength-high modulus polyethylene fibres and films, and liquid crystal-based processes. Experimental and theoretical results obtained with the system cellulose/amine oxide are presented to illustrate the potential and limitations of these fibre production methods.

Chanzy H., Presented at TAPPI '1983 International Dissolving and Speciality Pulps Conf.', held 5-8 April 1983 in Boston, M.A., pp 127-132

The Viskase Food Casings Patent (1992)

Nine years have elapsed since the last "Courtaulds" and "Amine oxide" patent was filed and this one is from Viskase, reminding us that we jointly developed a food casings film from the Tencel dope for sausage skins. However, there are no Courtaulds personnel among the inventors.  We started patenting soon after this one. Did Viskase encourage us? Did they also use Tencel dope to make a fibre-reinforced film for the wurst casings?

United States Patent
Nicholson ,   et al.January 11, 1994

Method of making a cellulose food casing

A cellulosic food casing formed by extruding a nonderivatized cellulose solution composed of cellulose pulp and an amine solvent into a seamless tube, contacting the inner and outer surfaces of the seamless tube with a nonsolvent liquid to precipitate a tube of nonderivatized cellulose and thereafter contacting the same with a water soluble softener. Apparatus for forming the food casing and a food casing of nonderivatized cellulose also are disclosed.

Inventors:Nicholson; Myron D. (Lemont, IL), Kajiwara; Edward M. (Skokie, IL), Ducharme, Jr.; Paul E. (Tinley Park, IL), McCallister; Merlan E. (Clarendon Hills, IL), Walta; Joseph R. (Lagrange, IL)
Assignee:Viskase Corporation (Chicago, IL)
Courtaulds Fibres Limited (Coventry, GB2
Appl. No.:07/822,506
Filed:January 17, 1992

Click here for the full patent

Tuesday, July 17, 2012


After the textile interests of the original Courtaulds became a separate company, production of viscose, acrylic and acetate fibres remained with the new Courtaulds plc within which is the Courtaulds Fibres Group. This consists of five businesses of which Courtelle (acrylic) and acetate are not widely used in the industrial textiles field, the remaining three are viscose, Tencel and Performance Products. The company is Western Europe's second largest producer of viscose with more than half its production going into the nonwovens and waddings market. A new US plant is to be built to produce Courtaulds solvent spun viscose fibre, Tencel. The Performance Products business produces speciality fibres mostly for industrial uses. The main product groups are the modacrylic, Teklan; the polyacrylate, Inidex; a high modulus acrylic fibre, Sekril and an anti-microbial fibre, Courtek M.

Anon, Tech. Text Mark., no. 2, July 1990, pp 7-22


The Courtaulds Viscose operations are still using Tencel as an example of forward-looking R&D and Lenzing is setting up a solvent-spun cellulose pilot line.  This also contains the first reference to the US Tencel plant.  At this point Lenzing appear to be 4-5 years behind Courtaulds in solvent spun development, but benefit from the knowledge that the NMMO process really can be made to work on a large scale.

European viscose producers are now reaping the benefits of major investment in research and development, process refinements, product development and environmental protection measures. In this article three leading European viscose producers - Courtaulds Fibres Viscose, Kemira Oy Sateri (Finland) and the Austrian company Lenzing AG consider recent developments in the viscose market and future company strategy. Amongst developments Courtaulds Fibres Viscose is researching into fibre finishes as well as new fibres such as the multi-limbed fibre developed under the Galaxy project. The US company Courtaulds Fibres Inc. recently announced the building of the first production plant for Tencel solvent-spun cellulosic fibre at Mobile, USA. Kemira Oy Sateri is now able to produce a chlorine-free viscose fibre in conjunction with Nordic pulp manufacturers. Lenzing AG is setting up a pilot-plant for a solvent spun viscose fibre marked by tenacity ratings on the same levels as synthetic fibres.

Anon, Nonwovens Rep. Int., no. 231, June 1990, pp 20, 23, 25

Sunday, July 15, 2012


A new generation of man-made cellulosic fibres have been launched onto the market by Courtaulds. The fibres are produced by a solvent spinning process and the method is chemically simpler than the production of viscose rayon. The new production method is described along with a comparison with other man-made and cellulosic fibres. Applications for the fibres are discussed. Emphasis is also placed on the benefits of these fibres to the spinning, weaving and dye finishing industries. A review is presented on the key market opportunities available to Tencel with special reference to textile and nonwoven applications.

This is a paper from the 1989 Dornbirn Conference, reprinted in the Lenzing house journal.  It is available on-line - click the reference above. 
Interestingly they publish the Q and A session from the conference which reveals some of the key issues at the time.


Courtaulds new Tencel fibre is produced by a new solvent process followed by new spinning, washing and drying technology. The finished product is highly consistent and free of by-product traces, and is one of the strongest staple cellulosic fibres. It is convertible into added value nonwovens by a variety of production routes. Tencel dry-laid fabrics have been made with half the latex bonding used on viscose, and gave stronger, more absorbent fabrics. Excellent strength properties, particularly in the wet state were achieved by blending Tencel with Hercules T151 polypropylene by thermal bonding. In the hydroentanglement process, Tencel outperformed the stronger polyester fibres. Its performance and possible applications are still being tested. 

Woodings C., Text. Month, Feb. 1989, pp 51-52


The changing fortunes of viscose may present problems for producers in Europe and worldwide. European producers such as Courtaulds, Lenzing AG and Hoechst AG have trimmed annual output over the last decade and taken steps to improve performance while keeping prices down. There are now signs that viscose is becoming more popular in the contemporary climate of environmental concern as it is based on a regenerative natural resource and is biodegradable, causing a surge in demand. New developments in viscose are underway such as Fibrafinn MS, a high quality fibre for high performance spinning equipment from Sateri, and Courtauld's extra strong tencel fibres. The background to the situation at Avtex Fibre US, now supported by NASA is outlined. 

 Anon, UK Text. News vol. 5, no. 6, 1988, pp 10-11

This is one of the few releases using "tencel" and including it with new developments in viscose. The capital letter was dropped when we hoped to use "tencel" as the generic name for solvent spun cellulose, to avoid having to call it rayon.  

Here also Avtex Fibres USA are mentioned as being supported by NASA.  I think they were in Chapter 11 at this time but were the only qualified supplier of viscose for carbonising to make rocket exhaust cones.  Avtex were still using the viscose process and the factories installed by Courtaulds in the 30's which had to be transferred to US companies under Lend-Lease during the war.


Here's the first release which mentions textile as opposed to nonwoven applications.

Tencel, a new cellulose fibre from Courtaulds, is produced from woodpulp by the company's patented solvent spinning route. It offers much higher yarn strengths than previously possible with rayons or even cotton, and its wet strength is almost the same as dry. It has a circular cross-section, making it particularly suitable for the new short staple spinning processes. Tencel is likely to find applications in the production of lighter weight apparel fabrics of superior quality, home furnishings and quality sheetings, and tehnical fabrics. Hydroentanglement produces a lofty, soft handling matt fabric, and thermal bonding also looks promising. Opening and intimate blending with other commercial fibres is easy. Tencel is environmentally friendly and biodegradable.

Anon, High Performance Text.,vol. 9, no. 7, Jan. 1989, pp 1-4

Since first posting this the original has surfaced and is added below:

Friday, July 13, 2012

Glyn Raven and the FTC

The CF0001 term was applied after the application to the FTC. Normal procedure after a new application. It was always considered that a new generic term would help in the promotion of the new fiber and we did not want to be associated with Rayon ( viscose) especially in the US.

The FTC head quarters are in LA on Wiltshire Bvd and I recall a couple of trips over there with Bob Feil to make our case. The FTC was represented by a cowboy booted bureaucrat called Brett something or other and he was supported by a british lecturer from Cal Tech - a fellow brit and ATI so I thought this would be easy. From the start it was obvious the technical advisor from Cal Tech had an entrenched position and thought this was just a new rayon or a cupro rayon since it was based on solvent spinning. We made the case that in all other production methods the cellulose undergoes chemical changes into an intermediary before dissolution and regeneration. As we all know Tencel is direct dissolution into the AO solution. 

I have no idea where the copy of the final application resides but it became a very long a technical document covering every aspect of the fiber from production to performance in fabrics, nonwovens , knits. 

The new generic was granted in 1995, just before I left Courtaulds, my parting shot from a 9 year association with Tencel which I left with very fond memories , lifelong friendships, about a million miles on Delta !! "

(From Glyn Raven - comment on LYOCELL - NOT TENCEL 1989)

Thursday, July 12, 2012

FTC Approves "Lyocell" For Use In Fabric Content Labeling (1996)

For Release: April 12, 1996
The Federal Trade Commission will allow clothing manufacturers and other marketers to use the name “lyocell” in the fiber content labels they are required by law to place in garments and other textile products sold in the United States. Although substantially similar in chemical composition to rayon, which must be dry-cleaned, lyocell is washable and is more resistant to shrinkage and wrinkling. The FTC also noted that other countries and international standards organizations allow use of the name lyocell.
Federal law -- the Textile Fiber Products Identification Act -- requires manufacturers to use the generic names of fibers contained in their textile products in the fiber content labels of those products. The FTC rules and regulations under this statute set out the definitions of the various names that can be used, as well as the process a manufacturer must go through to establish a new generic fiber name. Courtaulds Fibers, Inc. petitioned the FTC in January 1992 to add lyocell to the list of approved generic fiber names. In April 1992, the FTC issued a temporary designation which allowed Courtaulds to market the fiber without calling it “rayon.” Courtaulds subsequently performed various tests, submitted the results to the FTC, and in November 1995 the FTC published a notice in the Federal Register seeking public comment on the petition. All 27 comments received by the Commission, many of which were from industry members, supported the petition. Today, the Commission announced that it has formally amended the textile rules to add lyocell as a subclass of rayon.
Courtaulds is based in Axis, Alabama, and markets the new fiber under the trade name “Tencel.” The Commission vote to amend the Textile Act rules was 5-0.
(From the FTC website)

This post jumps forward in time but illustrates the length of time it took from deciding the generic name ought to be lyocell to getting it approved in the US.

...who chose the word lyocell?

FTC May Allow "Lyocell" For Washable Rayon (1995)

For Release: November 20, 1995

You soon may see the name "lyocell" in the fiber content labels of some of the clothes you purchase. The Federal Trade Commission has proposed to allow clothing manufacturers to use the new name for a fiber that, although substantially the same as "rayon" in terms of chemical composition, has significantly different characteristics. For example, lyocell is said to be washable, whereas rayon must be dry-cleaned. The FTC is seeking comments on the proposal, which it announced in response to a petition filed by Courtaulds Fibers, Inc., a manufacturer of lyocell based in Axis, Alabama, that markets the new fiber under the trade name "Tencel." The FTC proposal to allow the use of the term lyocell is consistent with the requirements of many other countries and international standards organizations.

According to an FTC notice to be published shortly in the Federal Register, garments made from lyocell are "highly resistant to shrinkage and wrinkling...," and therefore can be machine washed. These unique physical and performance characteristics are due to a special manufacturing process, the notice states. Under the proposal announced today, the FTC would permit manufacturers to use lyocell as an alternative to the generic name rayon for cellulose-based fibers manufactured under this process.The proposal contemplates an amendment to FTC rules and regulations under the Textile Act, with respect to the generic names and definitions that manufacturers can use in labeling textile fiber products. Under the proposed amendment, because of their chemical similarity, lyocell would be a subclass of rayon, rather than a whole new category.

Courtaulds had petitioned the FTC in January 1992 to add lyocell to the list of approved generic names, maintaining among other things that the fiber was in active commercial use in Europe under that generic name. As an interim response, in April of that year, the FTC granted the company a temporary designation to market the fiber. Thereafter, Courtaulds performed various tests and submitted the results to the FTC, which now is proposing the change to FTC rules.The Commission vote on the proposal was 5-0. Comments on the proposal will be accepted for 60 days after publication in the Federal Register. They should be identified as "Rule 7(d) Under the Textile Act -- Comment," and addressed to the FTC, Office of the Secretary, Room H-159, 6th Street and Pennsylvania Avenue, N.W., Washington, D.C. 20580.


The generic name allocated to the cellulosic fibre produced by Courtaulds Genesis solvent spinning process is to be Lyocell not Tencel. Lyocell is notable for its high wet strength. Its suitability for advanced nonwovens manufacturing systems, such as hydroentanglement, has been under evaluation.

 Anon, Nonwovens Rep. Int., no. 220, July 1989, p. 10

This little abstract hides a multitude of issues.  In 1988 I think we hoped to get Tencel as the generic but realised that Tencel was becoming too associated with Courtaulds and issued an edict that Tencel should become "tencel" in the literature to emphasise that it was not a brand. This failed.

I think CF001 became the temporary US generic before the FTC accepted lyocell, but what was the situation in the EU?  Finally lyocell became generic and Tencel the brand and I'll check the FTC site for more.  Had we got our way and Tencel had been accepted as the generic name, who knows what would the brand name would have been?

Wednesday, July 11, 2012

Pete Laity's patent (1983)

This is the first patent from a search with Courtaulds as the assignee name and "amine oxide" in the text.  The GB Patent had a priority date of June 1982 and the PCT was published in 1983.  The next patent with the same search terms came 10 years later. (I'm using USP's because they're easiest to cut and paste)

United States Patent
LaityApril 8, 1986

Polymer solutions

Shaped articles, such as fibres and films, are obtained from a polymer solution comprising cellulose, a solvent for the cellulose comprising a cyclic tertiary amine N-oxide and water, and a stabilizer for the solution selected from the group consisting of sodium hexametaphosphate, disodium hydrogen phosphate, potassium dihydrogen phosphate, hydroxy-ethylidene diphosphonic acid, aminoethyl diphosphonic acid, and complexes of such compounds with occluded metal ions present in the polymer solution. The stabilizer is present in an amount sufficient to stabilize the solution against thermal degradation which causes loss of solvent and discoloration of solvent and dissolved cellulose.

Inventors:Laity; Peter R. (Keresley, GB2)
Assignee:Courtaulds PLC (London, GB2
Appl. No.:06/579,886
Filed:February 8, 1984
PCT Filed:June 07, 1983
PCT No.:PCT/GB83/00151
371 Date:February 08, 1984
102(e) Date:February 08, 1984
PCT Pub. No.:WO83/04415
PCT Pub. Date:December 22, 1983

The full patent is at