What is viscose: a natural or synthetic fabric?

In short:

1. Viscose is a man-made fibre: plant cellulose, mostly from wood pulp, dissolved and spun again. EU Regulation No 1007/2011 lists it as number 25, among manufactured fibres.
2. Its agreed moisture allowance is 13%, against 8.5% for cotton and 1.5% for polyester: an absorbent, cool fibre with a fluid drape.
3. Modal and lyocell are regenerated cellulose too. Lyocell is made without carbon disulfide, with a solvent that is about 99% recovered.
4. Man-made cellulosic fibres reached 8.4 million tonnes in 2024, or 6% of world fibre production.

Viscose fabric is made from a man-made fibre. Its raw material is natural: cellulose from wood, sometimes from bamboo or other plants. But that cellulose is dissolved in a chemical bath, then spun again in a factory. So viscose belongs neither with natural fibres such as cotton or wool, nor with synthetic fibres such as polyester, which start from a synthesised polymer. It forms a third family, alongside modal, lyocell and cupro, often called regenerated or semi-synthetic fibres. On the label, EU law gives it a name of its own, defined by the way it is made.

Viscose, cotton, modal, lyocell, polyester: comparison table

The agreed allowance, set in Annex IX, is the moisture assigned to each fibre when labs calculate the percentages of a composition. It also works as a guide to absorbency: by these figures, viscose holds more moisture than cotton, and almost nine times as much as polyester.

Viscose: definition of a man-made fibre

Textile fibres fall into two broad groups. Natural fibres are harvested as they are from a plant or an animal. Man-made fibres are manufactured, and they split in two: regenerated fibres, made by chemically transforming a natural raw material, and synthetic fibres, spun from a polymer built from scratch. Viscose is the textbook regenerated fibre, and the encyclopedia entry on rayon describes rayon as a semi-synthetic fibre: natural in origin, industrial in production.

Regulation (EU) No 1007/2011 puts it in its own terms. Its Annex I sets out two tables: the first lists natural fibres (wool, cotton, flax, silk and others), the second manufactured fibres. Viscose is number 25, defined as a “regenerated cellulose fibre obtained by the viscose process for filament and discontinuous fibre”.

Viscose, rayon and artificial silk: one fibre, three names

The first “artificial silk” was the work of Frenchman Hilaire de Chardonnet, who patented his process in 1885, using nitrocellulose. Highly flammable, it gave way to the viscose process, patented in the United Kingdom by Charles Cross, Edward Bevan and Clayton Beadle in the early 1890s. Courtaulds began the first commercial viscose production in Coventry in 1905. The name rayon took hold in 1924, according to the French encyclopedia entry on viscose.

What the fibre composition label tells you

Under Article 14 of the regulation, every textile sold in the EU must carry a fibre composition label. Article 5 adds that only the names in Annex I may appear on it. Two practical consequences:

• a garment sold as “bamboo” cannot list “bamboo” in its composition: if its fibre is bamboo cellulose regenerated by the viscose process, the word on the label is “viscose”;
• the word “silk” may not be used to describe the look of a continuous filament yarn: “artificial silk” is a historical name, not a label term.

How viscose is made: from wood pulp to yarn

The manufacturing process starts from wood pulp with a cellulose content of around 87 to 97%. The main steps, as described in the encyclopedia entry on rayon:

1. The pulp is steeped in caustic soda (16 to 19% by mass) and becomes alkali cellulose.
2. It is pressed, shredded into “white crumb”, then aged in air, which shortens its molecular chains.
3. Carbon disulfide turns it into cellulose xanthate, the “yellow crumb”.
4. The xanthate, dissolved in a caustic solution, gives viscose proper, a thick liquid that is ripened, filtered and degassed.
5. Spinning means extruding it through a spinneret into a sulfuric acid bath, where the cellulose regenerates as filaments.
6. The filaments are drawn, washed, then cut into short staple fibres if needed.

That chemical step explains everything else: the hand feel, the behaviour in water and the environmental question.

Viscose vs modal vs lyocell vs cupro: what is the difference?

All four fibres share the same material, cellulose. What changes is how it is dissolved and spun again.

• Modal: the regulation defines it as regenerated cellulose made by a modified viscose process, with a high breaking force and a high wet modulus. In practice, the fibre is stretched while it is made, which aligns its molecules. High-wet-modulus viscose holds its dimensions and can be machine-washed.
• Lyocell: the cellulose is dissolved directly in an organic solvent, N-methylmorpholine N-oxide, without forming derivatives and without carbon disulfide. About 99% of the solvent is recovered, and the fibre is 50% more absorbent than cotton, according to the encyclopedia entry on lyocell. The trade name Tencel, owned by Lenzing, refers to this type of fibre.
• Cupro: the cellulose is dissolved by the cuprammonium process, based on copper and ammonia, before being spun again.

Among the alternatives to regular viscose, if you want a fibre that copes better with the washing machine, modal and lyocell are the two names to look for on the label.

Viscose properties: drape, fluid hand and absorbency

Viscose feels soft, smooth and cool on the skin. Its slippery, supple drape is closer to nylon than to cotton. That fluid hand is why it is used for wrap dresses, blouses and loose trousers: wide-leg or palazzo trousers cut from viscose crepe sway with every step.

On absorbency, its agreed allowance of 13% puts it above a cotton shirt, at 8.5%. It is breathable in the everyday sense: it soaks up sweat instead of letting it bead on the skin. It also takes dye very well, hence the wide range of colours and floral or graphic prints in viscose.

Is viscose warm?

Not really. Viscose does a poor job of insulating body heat, which makes it pleasant in hot, humid weather and cool to the touch, according to the textile classification handbook cited in the entry on rayon. It is a summer fabric. In winter, wear it as a lining, a base layer, or blended with wool.

Crepe, satin, twill, jersey: viscose fabrics

The same fibre changes character with the weave:

• viscose crepe: slightly grainy surface, heavy drape, ideal for dresses and fluid trousers;
• viscose satin: shiny face, for blouses and skirts;
• viscose twill: marked diagonal, a little more body for shirts;
• viscose jersey: soft knit for T-shirts and close-fitting dresses;
• velvet: velvet can be woven in viscose, as in a velvet dress with a deep sheen.

Shrinkage and creasing: why viscose moves in the wash

Shrinkage is the main complaint about viscose, and it has a physical cause. Regular viscose has the lowest elastic recovery of any fibre, and its strength drops once wet. A standard textile textbook even recommends dry cleaning only for regular viscose, while high-wet-modulus viscose such as modal can go in the machine (entry on rayon). Handled roughly in the machine, a regular viscose garment can shrink or lose its shape. High-wet-modulus fibres keep their dimensions when wet.

Creasing follows the same logic: with little elasticity, viscose holds wrinkles. On the plus side, it does not felt, unlike wool. Viscose shrinkage has nothing to do with boiled wool, which is felted on purpose with heat and friction.

A tip if you sew: wash fabric bought by the metre before cutting it. The shrinkage then happens to the fabric, not to the finished garment.

How to care for viscose

Day-to-day care comes down to a few habits:

1. Read the care label: its symbols follow the international standard ISO 3758. A “dry clean” instruction is there for a reason.
2. Wash cold or at 30 °C at most, by hand or on a delicate cycle, turned inside out in a mesh bag.
3. Never wring a wet garment: that is when the fibre is at its weakest.
4. No tumble dryer for regular viscose. Dry knits flat and woven shirts and dresses on a hanger, out of direct sun.
5. Iron while slightly damp, on the reverse, with the two-dot setting (150 °C at most under ISO 3758). Viscose tolerates heat, unlike acetate, which melts.

As with a sweater, these habits echo our guide to cashmere vs merino: lukewarm water, no wringing, gentle drying. The causes differ, the result is the same: a garment that keeps its size.

Is viscose eco-friendly?

The answer is mixed, and it depends mostly on the factory. Three points can be measured.

The chemical process. Carbon disulfide, used for viscose, is classified by France’s occupational health institute, INRS, as suspected of damaging fertility and the unborn child, and as causing damage to organs through prolonged or repeated exposure. In the 1930s, studies found significant health effects in 30% of American rayon workers. Emissions of this pollutant were estimated at about 250 g per kilo of rayon in 2004; carbon-bed recovery cuts them by about 90%, according to the entry on rayon.

Forests. Wood pulp raises the question of deforestation when the wood comes from poorly managed forests. The EU Ecolabel for textiles sets benchmarks: a minimum of 25% of pulp fibres from sustainably managed forests, the rest from legal sources; a minimum of 50% of pulp from mills that recover value from their spent liquors; and no more than 30 g of sulphur emitted to air per kilo of staple fibre, as an annual average.

End of life. Viscose is still cellulose. A North Carolina State University team found that cellulose-based knits released 0.2 to 4 mg of microfibres per gram in accelerated laundering, against 0.1 to 1 mg for polyester (Marine Pollution Bulletin, 2019). But rayon yarns biodegraded by over 70% in lake water and about 50% in seawater, while polyester did not degrade appreciably (Marine Pollution Bulletin, 2020).

Worldwide, man-made cellulosic fibres reached 8.4 million tonnes in 2024, or 6% of the 132 million tonnes of fibre produced, far behind polyester at 59%, according to the Textile Exchange report summarised by the EU Textiles Ecosystem Platform. For a more eco-friendly viscose, look for the EU Ecolabel or an FSC or PEFC forest certification on the product page, or switch to lyocell.

Choosing a viscose garment

• For summer: 100% viscose, in crepe or twill, for its coolness and absorbency.
• For easy washing: modal or lyocell, the two alternatives that cope best with water.
• For a dressy outfit: viscose satin or velvet, sent to the dry cleaner if the label says so.
• When ordering online: regular viscose can lose a little length in the first wash; keep the women’s size conversion chart at hand and compare the brand’s size guide measurements before choosing between two sizes.

One last habit: turn the label over before you buy. “Viscose”, “modal” or “lyocell”: three words for three ways of making the fibre, and three ways of washing the garment.