Lesson · Viscose · Modal · Lyocell

All three are made from wood pulp, dissolved and spun into fiber. The difference is the process, and that changes almost everything.

• Is viscose the same as rayon?Yes. Viscose is the most common kind of rayon. US labels often say “rayon”, and European labels say “viscose”. More on the rayon family
• Viscose: the originalMade since 1905. It’s soft and drapey, but it’s weak when wet (it loses about half its strength). It’s also made with carbon disulfide, which has harmed factory workers. Overall C.
• Modal: viscose, refinedA viscose that’s stretched as it’s spun, often from beech wood. It’s stronger than viscose, especially when wet, and holds its shape better. Overall B.
• Lyocell: the clean processA different solvent, with no carbon disulfide, used in a closed loop. TENCEL™ says more than 99.8% of the solvent is recovered and reused. It’s strong, soft and breathable. Overall A, the best of the three.
• Is it natural or synthetic?Neither. They’re semi-synthetic: a natural source, made by a chemical process. None of them is plastic, so they shed fibers in the wash but not microplastics.
• Which is best for skin?All three absorb moisture well and feel cool and soft. Skin & comfort: A.
• TENCEL™ vs cotton?TENCEL™ Lyocell is an A, like organic cotton, and above regular cotton (B). That’s mainly because it needs far less water and fewer chemicals. More on cotton
• Which one should I choose?Lyocell first. Then modal or viscose with a named standard. Plain viscose last.
• Our gradesViscose · C
  Water C · Chemicals D · Climate C · Durability D · Back to nature B · Microplastics A · Skin & comfort A.
  Modal · B
  Water C · Chemicals C · Climate B · Durability C · Back to nature A · Microplastics A · Skin & comfort A.
  Lyocell · A
  Water A · Chemicals A · Climate B · Durability B · Back to nature A · Microplastics A · Skin & comfort A. How we grade
• What to look forTENCEL™ Lyocell or TENCEL™ Modal. For viscose, LENZING™ ECOVERO™, which uses at least 50% less water and greenhouse gas than generic viscose. FSC for the wood. Check a piece with the Clothing Check

Sources: TENCEL™ · LENZING™ ECOVERO™ · Changing Markets, Dirty Fashion · Rayon (Wikipedia) · Modal (Wikipedia) · Shuvo 2020