What is viscose fabric? The plant-based fiber that isn't natural

What is viscose fabric?

What is viscose fabric? Viscose, also sold as rayon, is a semi-synthetic fiber spun from regenerated wood cellulose. It is not natural like cotton or fully synthetic like polyester, but something in between: plant matter that has been dissolved in harsh chemicals, then reformed into a soft, silk-like thread.

That middle ground is the whole story. Viscose begins as a renewable raw material, usually wood pulp from eucalyptus, beech, pine, or bamboo, but it only becomes fiber after an industrial chemical process. Textile scientists call this category regenerated cellulose. The word viscose comes from the thick, honey-like liquid the cellulose turns into partway through production. On a US care label you will often see rayon, while a European or UK label usually says viscose, and in everyday use they mean the same thing. It was first developed in the late nineteenth century as an affordable alternative to silk, which is why it is sometimes called artificial silk.

How viscose is made from wood pulp

The viscose process has barely changed in over a century, and every step shapes how the fabric behaves and whom it affects.

First, wood is reduced to dissolving pulp, a sheet of nearly pure cellulose. That pulp is steeped in caustic soda (sodium hydroxide), which converts it into alkali cellulose. Then comes the step that defines conventional viscose: the alkali cellulose is treated with carbon disulfide to form a compound called cellulose xanthate. Dissolved in more caustic soda, it becomes the viscous, amber solution that gives the fiber its name.

This viscose liquid is forced through a spinneret, a metal plate studded with tiny holes, into a bath of sulfuric acid and salts. The acid regenerates the cellulose, hardening the extruded streams back into solid filaments. Those filaments are washed, bleached, cut or left as continuous yarn, and finally spun, then woven or knitted into cloth. Two chemicals do the heavy lifting here, caustic soda and carbon disulfide, and both are central to why viscose is controversial.

The pros and cons of wearing viscose

Viscose earns its place in closets for good reasons. It is soft, breathable, and lightweight, with a fluid drape that mimics silk at a fraction of the cost. It is highly absorbent, so it feels cool against the skin in warm weather, and it takes dye beautifully, holding rich, saturated color. Because it is cellulose, it is also biodegradable under the right conditions, unlike petroleum-based synthetics. You will find it in dresses, blouses, linings, scarves, and soft furnishings, and it is often blended with cotton, polyester, or spandex to improve durability and stretch.

The drawbacks are just as real. Viscose is weak when wet, losing much of its strength in the wash, which is why garments can shrink, stretch, or tear more easily than cotton. It wrinkles readily, can water-spot, and may lose its shape if tumble-dried on heat. It is also prone to pilling over time. None of this makes viscose a bad fabric, but it does make it a high-maintenance one that rewards gentle handling.

Viscose vs modal, lyocell and polyester

Viscose is the oldest member of a family, and its relatives were engineered to fix some of its flaws.

Modal is essentially an upgraded viscose. It is made by a similar process, but the fibers are stretched during production to align the molecules, which makes modal stronger, especially when wet, as well as softer and more resistant to shrinking. It still relies on carbon disulfide chemistry.

Lyocell, best known under Lenzing's Tencel brand, is the bigger leap. Instead of carbon disulfide, lyocell dissolves cellulose in a non-toxic organic solvent called NMMO (N-methylmorpholine N-oxide), in a closed-loop system that recaptures more than 99 percent of the solvent for reuse. The result is a stronger, highly absorbent fiber made with far less chemical waste.

Polyester is the outsider. It is a true synthetic spun from petroleum, not plants. It is durable, wrinkle-resistant, and quick-drying, but it breathes poorly, can feel clammy, and sheds plastic microfibers that do not biodegrade. In short, viscose breathes better and feels more natural, while polyester is tougher and lower-maintenance.

The environmental and labor problems with conventional viscose

This is where the idea that viscose must be green because it comes from trees falls apart. Because it begins as wood, viscose carries a deforestation risk, and campaigners have linked some supply chains to ancient and endangered forests. That is why certifications such as FSC and programs like Canopy's CanopyStyle exist.

The larger problem is the chemistry. Carbon disulfide, central to conventional viscose, is toxic and has been studied as an occupational hazard for more than a hundred years. The Changing Markets Foundation's Dirty Fashion investigations describe it as an endocrine disruptor linked to serious illness in exposed workers, from Parkinson's-like symptoms to heart disease and stroke. On-the-ground reporting in India, Indonesia, and China documented factories dumping untreated wastewater into local lakes and rivers, harming the communities around them.

Cleaner options exist. Closed-loop lyocell, Lenzing's EcoVero, and viscose made in plants that capture and recycle their chemicals all cut the damage sharply. The practical takeaway is simple: viscose is not automatically eco-friendly, and the brand and production method matter far more than the plant it started as.

How to care for viscose so it lasts

Because viscose is fragile when wet, careful laundering is the difference between a garment that lasts and one that warps. Check the label first, since a fair amount of viscose is dry-clean only.

If it is washable, hand wash or use a gentle, cold cycle with mild detergent, and skip aggressive wringing. Do not tumble dry on heat, which is the fastest way to shrink viscose. Instead, reshape the garment while damp and dry it flat or on a padded hanger, away from direct sun. Iron on a low setting, inside out and while slightly damp, and store heavier knits folded rather than hung so they do not stretch. Never bleach viscose, and keep it away from high heat, which can scorch or permanently shrink the fibers. Treated gently, viscose holds its drape and color for years.