Fibres · Man-made
Lyocell / Tencel
Cellulose reborn the clean way: soft, lustrous and with a fluid fall, it is the most eco-friendly version of viscose. It has little elasticity, so it is at its best in cool, drapey garments rather than in ribbing.
Translated from Italian. A native knitter has not reviewed this translation yet.
History
It began as an evolution of viscose fibres, but with a different process: wood pulp is dissolved in an organic solvent (amine oxide) that is recovered and reused in an almost closed loop, without the heavy chemistry of traditional viscose. The best-known version carries the Tencel brand, now the trade synonym for lyocell in knitwear and quality fabrics.
How the yarn is made
The wood is reduced to pulp and dissolved into a cellulose solution that is extruded through spinnerets, giving continuous filaments that are then usually cut into staple for spinning. It is not a fibre that is shorn or combed like animal fibres: its fineness and length are set during production, and that is exactly where the smooth, even quality of the yarn comes from.
Why it is prized
It combines qualities that rarely go together: the cool, lustrous hand of a fine plant fibre, a fluid drape that falls beautifully, and remarkable strength even when wet, higher than viscose. It also handles moisture well, staying pleasant on the skin in summer and between-season garments.
Dyeing
Excellent. Being pure cellulose it takes reactive and direct dyes very well, with deep, bright and even colours. The smooth surface enhances saturation and gives dyed yarns a silky lustre that is hard to achieve with duller fibres.
Care
Handle it gently: hand wash or a delicate cycle in cold water, without hard twisting, and dry flat because when wet it gives and stretches. It tends to fibrillate slightly on the surface with rubbing, which can create a peach-skin fuzz or light pilling: avoid abrasion and aggressive spin cycles.
End of life
It is cellulose from wood and, if not blended with synthetic fibres, it is biodegradable and compostable. Sourcing from responsibly managed forests and the recovered-solvent process make it one of the most sustainable choices among regenerated cellulose fibres.
How to recognise it
| Hand | Soft, cool and smooth, with an almost silky slip and a cooler touch than animal fibres. It has no springiness: it feels yielding and relaxed under the fingers. |
|---|---|
| Look | Lustrous and even, with a silky sheen and no visible crimp. The yarn looks regular and compact, with no woolly halo. |
| Behaviour | It falls fluidly and heavily, drapes beautifully but recovers little after stretching; when wet it lengthens and needs to be laid flat again. It creases more than synthetics but less than linen. |
| Burn test | Cellulosic signature: it burns quickly with a bright flame, smells of burning paper or wood, leaves a little crumbly grey ash, and does not melt into a bead. |
| Home tests | Burn test: quick flame, smell of burning paper, light ash with no melted bead · Wet stretch test: the fibre weakens and lengthens, a cellulosic sign · Touch test: cool, smooth and slippery, without the springiness of wool |
| Confused with | Viscose, almost identical by hand but weaker when wet and less resistant to abrasion · Silk, for lustre and coolness, but silk shows a protein signature in the flame and smells of burning hair |
| Only in a lab | Telling lyocell, viscose, modal and cotton apart with certainty requires a laboratory, because they are all cellulose and share the same burn signature: microscopy and chemical analysis are needed (ISO 1833). |
Physical facts
| Property | Value | Source |
|---|---|---|
| elastic memory | None | research |
| sag | High | research |
| halo | None | research |
| felting risk | None | research |
| fineness (µm) | 11–15 | estimate |
| moisture regain (%) | 11.5 | research |
| typical shrinkage (%) | 0–8 | estimate |
| staple length (mm) | 38–40 | research |
measured = a measurement with a reference · iso = a standard · research = a verified source · estimate = plausibility only
Good for
fluid, drapey garments · cool summer knitwear · tops and dresses with a lovely fall · blends with cotton or wool for softness and slip
Less good for
ribs and cuffs that must spring back · garments needing a lot of elastic memory · structures that must carry weight without sagging