Lyocell: the wood fibre explained

In short:

1. Lyocell is a man-made fibre produced from wood pulp, most often eucalyptus.
2. The cellulose is dissolved in an organic solvent recycled in a closed loop.
3. Tencel is a registered trademark of the Lenzing group; lyocell is the name of the fibre.
4. It is soft, fluid, absorbent and strong, including when wet.
5. It is washed at low temperature, without a tumble dryer, to keep its feel.

Lyocell appears more and more often on clothing labels, from fluid shirts to wide trousers and even jeans. This fibre made from wood sits apart between natural fibres such as cotton and linen, and synthetic fibres such as polyester. Understanding where lyocell comes from, how it is made and how it behaves when worn helps to choose pieces that last, and to care for them properly.

Lyocell, viscose, modal and cotton: the comparison table

Lyocell belongs to the family of regenerated cellulose fibres, like viscose and modal. The table below places it alongside these two relatives and cotton, the natural fibre it is most often compared with.

What is lyocell?

Lyocell is a textile fibre made from the cellulose contained in wood. The trees used are mainly fast-growing hardwoods, first and foremost eucalyptus, but also beech or birch. The wood is turned into pulp, the cellulose is extracted and dissolved, then spun into continuous fibres.

It is called a man-made fibre rather than a synthetic one: the raw material comes from plants, but it goes through an industrial transformation before becoming a yarn. The logic is the same as for viscose, with a different process.

A name framed by regulation

In the European Union, Regulation (EU) No 1007/2011 sets the list of fibre names allowed on a label. Lyocell appears under its own name, defined by its organic solvent manufacturing process. A garment labelled lyocell therefore meets a precise definition. The article on clothing labels explains what this information must show.

Lyocell and Tencel: what is the difference?

The two names are often used interchangeably, but they do not mean the same thing. Lyocell is the generic name of the fibre, which any manufacturer can use. Tencel is a registered trademark, now owned by the Austrian group Lenzing, which notably covers its lyocell fibre (Tencel Lyocell) and its modal fibre (Tencel Modal).

A fibre born in the late 1980s

Lyocell was developed in the laboratories of the British company Courtaulds, which first produced it in 1988. It went on sale in 1992 under the name Tencel. The Lenzing group then developed its own production and later took over the brand. Other manufacturers also produce lyocell under their own trade names.

How lyocell is made

The manufacture of lyocell follows a few main steps, which explain both its qualities and its reputation as a lower-impact fibre than viscose.

1. Pulp preparation: the wood is chipped and turned into cellulose pulp.
2. Dissolution: the cellulose is dissolved directly in an organic solvent, N-methylmorpholine N-oxide (NMMO). The resulting solution has a consistency close to honey.
3. Spinning: the solution is pushed through a spinneret with tiny holes, then into a bath where the cellulose sets into filaments.
4. Washing and solvent recovery: the fibres are rinsed and the solvent is recovered to be reused.

A closed-loop process

What sets lyocell apart is this fourth step. The solvent is recovered and fed back into production, which is known as a closed loop. The recovery rates reported range from about 97 to 99 % depending on the source. The process also avoids the carbon disulphide used to make conventional viscose.

How lyocell feels to wear

What makes lyocell worthwhile in a lasting wardrobe is its balance between comfort and durability.

• A soft, smooth feel: the surface of the fibre is even, which feels pleasant directly on the skin.
• A fluid drape: lyocell drapes naturally, hence its use for shirts, dresses and wide trousers.
• Good moisture absorption: the fibre absorbs moisture then lets it evaporate, which reduces the clammy feeling.
• Good strength: unlike viscose, lyocell stays strong when wet, which helps it withstand washing.
• Moderate creasing: it creases less than linen and recovers its shape fairly quickly as it is worn.

A fabric for every season

Thanks to the way it manages moisture, lyocell works as well in summer, where it stays cool, as in between seasons as a middle layer. For winter pieces, it pairs easily with wool: a wool jumper over a lyocell shirt makes a layering that is both warm and breathable. The guide on how to wash wool then helps to care for these pieces.

Lyocell and the environment: what to know

Lyocell is often presented as a more responsible fibre than conventional viscose or conventional cotton. Several factors support this, others call for nuance.

The positive factors

• A renewable raw material: the wood comes from fast-growing trees, often from managed and certified forests.
• A recycled solvent: the closed loop reduces the waste linked to manufacturing.
• A biodegradable fibre: pure lyocell is cellulose-based and breaks down under suitable conditions.

Points to keep in mind

• Blends: a fabric combining lyocell with polyester or elastane loses some of these advantages, biodegradability in particular. The exact composition is on the label.
• Dyes and finishes: they weigh on the impact of the finished garment, whatever the starting fibre.
• Lifespan: a garment worn for a long time remains the most effective lever. The pointers to recognise a sustainable fashion brand help to sort things out.

How to care for a lyocell garment

Lyocell handles washing well, but it keeps its feel better with a few simple habits.

• Washing: in the machine on a delicate cycle at 30 °C, or by hand in lukewarm water. Always follow the care label first.
• Turn the garment inside out: this protects the surface from friction in the drum.
• Gentle spin: a moderate spin avoids marking the fabric.
• No tumble dryer: dry flat or on a hanger, out of direct sunlight.
• Ironing: at low or medium temperature, on the reverse, or with steam.

Avoiding the peach-skin effect

With repeated friction, the surface of lyocell can become covered in tiny fibrils that give it a slightly fuzzy look, known as the peach-skin effect. Washing the garment inside out, with pieces of a similar fabric and without overloading the drum, limits it.

Which garments to choose in lyocell

Lyocell lends itself above all to pieces that call for movement and fluidity.

• Shirts and blouses: they benefit from its drape and comfort on the skin.
• Fluid trousers: a pair of wide-leg trousers in lyocell moves with each step and creases little during the day.
• Dresses and long skirts: the fabric drapes without clinging.
• Denim: blended with cotton, lyocell softens the canvas of a pair of jeans and makes it more fluid.

To compare lyocell with the other common fabrics of the wardrobe, the guide linen, cotton or viscose sets out their respective uses.

Frequently asked questions