Yuki Sleep · Field Notes · N° 02
Sleep under a forest.
Organic lyocell, spun from eucalyptus. An investigation into the quietest fibre we know — and what it does for the eight hours you can't watch.
01 — The fibre
Grown, not synthesised.
Lyocell begins as eucalyptus — FSC®-certified groves on land too poor for food crops, watered by rain alone.S6
The wood becomes pulp. The pulp becomes a fibre smoother than cotton and more absorbent than either. Nothing petroleum-born. Nothing that sheds plastic into your bed.S2S3
02 — The loop
A fibre that keeps its solvent.
Most textiles leave their chemistry behind. Lyocell is spun in a closed loop — the solvent is captured and used again, at a recovery rate of at least 99%.S1
03 — The night lab
What happens under the duvet.
Your bed has a climate. Research associates a stable 40–60% humidity near the skin with unbroken sleep. Drag through the night — watch three fibres manage the same sleeper.S4
04 — The evidence
The case for bedding that breathes.
Manufacturer data on TENCEL™ lyocell's moisture uptake against cotton.S2
Lyocell holds and releases water vapour; polyester holds almost none — it stays at the skin.S2
Research associates a stable bed microclimate with fewer awakenings.S4
A drier microclimate is associated with an environment less favourable to mites and bacteria.S5
05 — Skin & hair
Smooth is kind.
Under a microscope, cotton is a twisted ribbon. Lyocell is a smooth, round fibril — less friction against skin and hair, which is why smooth cellulosic textiles are so often recommended for sensitive skin.S3
You don't feel a fibre. You feel the absence of one.
06 — Three fibres
Same bed, different night.
Cotton is honest company — we sleep under it too. Polyester is the one we won't touch.
07 — The edit
The quietest bed you'll own.
Premium lyocell sets, woven for Yuki. Cool in summer, warm in winter, honest in every season.
Sleep under it →30-night trial · OEKO-TEX® Standard 100
08 — Asked, answered
Honest questions.
Is lyocell the same as TENCEL™?
Is lyocell organic?
Does it feel like silk or like cotton?
Who is it for?
Sources
Proof, not adjectives.
- Lenzing AG. TENCEL™ closed-loop production — ≥99% solvent recovery. Technical literature.
- Morton & Hearle, Physical Properties of Textile Fibres. Moisture regain: lyocell ~11–13%, cotton ~7–8%, polyester ~0.4%. "+50% vs cotton" is Lenzing manufacturer data.
- Dermatological textile literature. Smooth cellulosic fibres and reduced friction on sensitive skin. Association, not a medical claim.
- Okamoto-Mizuno & Mizuno (2012), Journal of Physiological Anthropology. Bed microclimate (temperature, ~40–60% RH) and sleep continuity.
- Arlian et al. House dust mite populations and sustained humidity ≥70% RH; Lenzing hygiene testing, lyocell vs synthetics.
- Lenzing sustainability reporting. FSC® certification; rain-fed eucalyptus on marginal land, no irrigation or pesticides.
- TÜV Austria. Biodegradability certifications (soil, industrial, marine) for TENCEL™ lyocell.
- Lenzing LCA / Higg MSI. Water footprint of eucalyptus lyocell vs conventional cotton.
The Night Lab is a modelled illustration built from S2 and S4 — not a laboratory measurement of Yuki products.