TENCEL
A brief insight into the world of (z)cellulose fibres.
Regenerated fibres - what are they?
Regenerated fibres are fibres made from regenerated cellulose (wood). These include viscose, modal, cupro and lyocell/TENCEL®.
Other regenerated fibres
Regenerated fibres are fibres that are produced from naturally occurring, renewable raw materials using chemical processes, primarily cellulose derivatives from wood.
"Regenerated fibres are an established and popular material for clothing and nonwovens."
The raw material
Regenerated fibres are fibres that are produced from naturally occurring, renewable raw materials using chemical processes. Together with synthetic man-made fibres, they are classified as man-made fibres and are therefore not natural fibres.
The current share of man-made fibres in the global production volume of textile fibres is around 70%. Cellulose fibres account for around 10 % of this.
Cellulose fibres such as viscose and lyocell are mainly produced from wood by first dissolving the resins and waxes contained in the wood. A complex process is then used to produce a mass that is pressed through nozzles. The resulting fibres are cleaned and bleached before they are used for the production of textiles. LENZING AG from Austria has developed a much more environmentally friendly production process in which water consumption is significantly lower than in the production of conventional cotton. Its environmental impact is comparable to that of the production of organic cotton.
The development
Properties of cashmere
Until around 1900, natural fibres were used almost exclusively for the Manufacturer of clothing and home textiles. As early as 1734, efforts were made to produce artificial silk (including by René-Antoine Ferchault de Réaumur), but without any significant success. In the 1860s, there was a crisis in silk production in Europe as silkworms were affected by a disease. The Frenchman Hilaire de Chardonnet was looking for a solution to this problem. In 1885, he discovered that cotton consists of 92% cellulose. This discovery was based on his intensive study of the behaviour of silkworms.
He liquefied the cellulose fibres of the cotton and pressed the resulting liquid through spinnerets in the same way as silkworms produce spinning thread.
In 1898, a new process was patented - the viscose process. Since then, work has been ongoing to improve and develop new fibres and achieve new fibre properties.
VISCOSE/RAYON
For the next 40 years, the fabric was known in English-speaking countries as "Artificial Silk". At the beginning of the 20th century, a committee set up by the US Department of Commerce was tasked with finding a more memorable name to describe the fibre.
In 1924, this committee decided on the name "Rayon". This is a compound word consisting of the word "ray" and the final syllable of "cotton". For the German market, the spelling was changed to "Reyon". However, this name never fully caught on in Germany, where the fabric is known as viscose (viscose). For clothing and textiles of American or international origin, however, the name "rayon" is still used in the textile labelling.
Viscose is also known as rayon because its basic material is cellulose. Wood species such as pine, Books, eucalyptus or spruce are used here. The wood is soaked in caustic soda to break down the cellulose. After the further addition of carbon disulphide, a viscous mass is produced, which is pressed through nozzles to create a thread. The end product consists of 90% natural cellulose and the other components wax and pectin. The special properties of viscose are the fineness of its fibres (10 to 15 μm diameter) and its good moisture absorption, which makes it a very hygienic material. Typically, the fibres have a fineness of 0.5 to 30 dtex. How fine the fibres become depends on the diameter of the nozzle through which the spinning solution is pressed.
By processing the cellulose in the viscose process, the characteristics of the fibre can be varied, which is not possible with the natural fibre cotton. The fibres are extremely uniform, can be dyed easily and retain their intense colour for a long time.
The natural raw material gives viscose many positive properties. Textiles made from viscose are very breathable and absorbent. Viscose fibres have the ability to absorb up to 400% of their own weight in water.
The material is suitable for Allergens, does not fluff and absorbs sweat very well. Viscose is soft, light and yet robust. Viscose fabric is visually reminiscent of cotton fabric, but has a much greater lustre, is softer to the touch and has a more flowing drape.
However, viscose is also very susceptible to creasing and does not retain its shape.
LYOCELL/TENCEL®
Lyocell is a natural material made from wood cellulose (pulp). This is done using an advanced solvent spinning process, which was first developed in 1972 in the now closed Enka fibre mill in the USA. It was marketed in the United States under the name "Tencel" by the company Courtaulds and later sold to the Austrian company Lenzing AG, a textile giant and the world's largest lyocell producer. After many years of preliminary research work, Lenzing started construction of its first lyocell fibre pilot plant in 1990, opening a whole new chapter in its corporate history. For the first time, a high-quality botanic fibre could be produced in Lenzing using a particularly environmentally friendly process. Since the 1990s, this miracle fibre has been used as a material for the textile industry.
Lyocell superfibre
Lyocell or Tencel® is the most sustainable synthetic fibre!
Tencel is also clearly superior to conventional cotton from an ecological point of view. While more plant toxins are used in the manufacture of cotton than in any other cultivated product, the eucalyptus plant remains free of chemical additives.
TENCEL® is a registered trademark of the Austrian company Lenzing AG for Lyocell. Lyocell is an industrially but ecologically produced material obtained from the wood of the eucalyptus tree. The cellulose required for the Manufacturer of Lyocell comes from Asian eucalyptus wood, which is grown in controlled and sustainable forestry. The soil conditions here do not permit any other agricultural use and so no fields are "consumed" that could also be used for growing food - unlike when growing cotton.
The wood is particularly ecological as the trees grow very quickly. As eucalyptus is naturally resistant to pest infestation, pesticides are not used. Eucalyptus not only requires no pesticides, but also no fertiliser and no artificial irrigation. As a result, considerably less water (only 1/20) is used than in cotton production. Independent studies have calculated that around 2000 litres of water are needed to produce a normal cotton Tees & polos. The eucalyptus plant requires ten to twenty times less. And the fibre yield is up to ten times more effective when measured against the land.
Extraction
The sustainable, "non-toxic" production of TENCEL®
The undemanding, natural base material is processed in a very environmentally friendly way.
For Manufacturer, small shreds are cut from the eucalyptus wood and soaked in a solution of amine oxides to dissolve out the cellulose. Water and a non-toxic solvent are added to produce a pulp slurry, which is then heated under vacuum, removing the water and filtering the resulting "spinning solution". In the form of a clear spinning solution, the cellulose is pressed through spinnerets and collected as continuous fibres in a spinning bath. These fibres can now be spun into yarn or treated further.
This spinning process is known as the "WET SPINNING PROCESS":
The entire production process is a closed cycle. The water is removed again and the solvent released from the fibre is one hundred percent biodegradable - but 99.5 percent of it is initially reused.
Properties
TENCEL® is characterised by features that make it a real competitor to long-established fibres. Thanks to its so-called fibril structure (small hairs), the fibre is a perfect moisture manager. This means that the tiny hairs quickly wick moisture away from the skin. For example, it absorbs 50% more water than cotton and effectively wicks it away from the body. The fibres ensure an optimum skin climate, they have a warming effect in cold temperatures and a cooling effect in hot temperatures. This has the advantage that the body temperature can be kept more or less constant during sport.
By wicking away moisture, the fabric is also resistant to bacteria and unpleasant odours.
The fibre has a smooth, silky feel, warms as well as wool, cools like linen and is more absorbent than cotton. The fibre does not crease, is tear-resistant and durable. Tencel® is also breathable and is therefore ideal for sportswear.
And all without any chemicals.
The fibre is often combined with other materials to give it additional properties.
For example, the fibre's low crease tendency is responsible for the almost non-existent wrinkling of "non-iron" Shirts and Blouses after washing. This is caused by the voluminous swelling of the material when wet.
Tencel® is 100 % biodegradable.
Modal
Modal is a fibre obtained from beech wood and produced using a modified viscose process. While the related viscose can be made from various raw materials, only beech wood is used for modal, which is why fibres of this type are stronger than viscose both dry and wet. The wood is first debarked and broken down into small chips. These are then processed into a cellulose mass in a multi-stage chemical dissolving process and then spun by machine into a pure cellulose fibre material with the help of spinnerets.
Modal fibres have a very smooth surface, are extremely soft and have a matt-silky sheen. Their feel is strongly reminiscent of silk.
Even though modal is closely related to viscose due to its chemical composition, the properties are different. Modal fabrics are stronger, smoother and more absorbent, more breathable and more heat-resistant than viscose fabrics. They are very elastic, hard-wearing, dimensionally stable, insensitive to heat and easy to care for.
The main advantages of modal are that it feels good to wear and is comfortable to wear, as the fabric has an excellent water absorption capacity and also wicks away moisture quickly. The moisture absorption of modal is even around 50% higher than that of cotton. The smooth modal fibres also ensure a high level of comfort for Allergens and people with sensitive skin.
The natural fibre is manufactured purely by machine using a chemical process, which is why the fabric is classified as a chemical and synthetic fibre despite its natural origin. More precisely, it is a cellulosic man-made fibre because, like viscose, it is made from 100% cellulose.
Cupro
Cupro is also known as copper silk or copper fibre and has similar properties to viscose. The textile fibre consists of a mixture of copper, ammonia and cellulose.
As early as the middle of the 19th century, the chemist Professor Mathias Eduard Schweizer discovered that cellulose could be dissolved in a special copper oxide-ammonia compound. However, it was not until 1897 that the process was patented by Max Fremery and Johann Urban - as a filament in light bulbs.
It was only two years later that the development of copper silk had progressed to the point where it could also be used in the textile industry.
In 1902, Fremery and Urban gave up the production of filaments and devoted themselves entirely to the manufacture of artificial silk. In 1910, they bought the Fürst Guido von Donnersmarck artificial silk and acetate works near Szczecin, at the same time acquiring the viscose patents held there in order to experiment with and optimise them. In the years that followed, they made decisive progress with the business idea.
In the 1980s, cupro textile production in Germany was replaced by modern technologies and textiles. The reason for this was the relatively high production costs and ecological aspects.
Instead, viscose or other textile fibres were increasingly used, but cupro can still be found in imported goods.
Cupro is manufactured using a copper oxide-ammonia process, also known as the Cuoxam process. In this process, cellulose is dissolved in an ammonia solution. This produces a viscous liquid containing 4 % copper, 29 % ammonia and 10 % cellulose, which is pressed into fast-flowing, warm water. This produces the fine cellulose threads. This spinning process is known as the draw spinning process. Finally, the copper ions are removed and the threads are rinsed with highly diluted sulphuric acid.
Cupro is particularly suitable as a lining fabric as the fibres are breathable, antistatic and moisture-binding. Another advantage of Cupro as a lining fabric is its soft, smooth and silky feel - ideal for summer textiles.
Acetate/triacetate
Although acetate is a chemically produced fibre, it has a natural origin. The acetate consists mainly of dried cotton or beech wood. Both materials are ground into a fine cellulose powder in the same process and esterified with acetic acid. Although cellulose acetate is obtained from wood, it is not a natural fibre.
In the 1930s, synthetic fibres became known as an inexpensive substitute for silk.
A further development of cellulose acetate is triacetate. Triacetate fibres have the same positive properties as acetate fibres, but are more heat-resistant in comparison and can therefore be ironed and pleated.
- Acetate (CA) is produced in a dry spinning process from cellulose acetate previously dissolved in acetone.
- Triacetate (CTA) is also produced in a dry spinning process from cellulose acetate previously dissolved in dichloromethane.
Textiles made from acetate are similar in structure, Optics and feel to fabrics made from natural silk. They are smooth, highly lustrous, dimensionally stable, virtually crease-free, flowing, extremely stretchable and resilient and impress with their high resistance to light. Due to their low swelling content, they absorb very little moisture and are slightly dirt-repellent. Due to their soft feel and outstanding gliding properties, they are often used as linings. Due to their moisture-repellent properties, acetate fibres are also suitable for the manufacture of Umbrellas and rain jackets.
Textiles made from acetate are similar in structure, Optics and feel to fabrics made from natural silk. They are smooth, highly lustrous, dimensionally stable, virtually crease-free, flowing, extremely stretchable and resilient and impress with their high resistance to light. Due to their low swelling content, they absorb very little moisture and are slightly dirt-repellent.
Due to their soft feel and excellent gliding properties, they are often used as linings, while their moisture-repellent properties also make acetate fibres suitable for the manufacture of Umbrellas and rain jackets.