How Do You Wash Viscose Without Ruining It?
Temperature, washing machine program, and hand-wash rules that protect the fiber from shrinking and loss of strength
This is the question that most often comes up just before the first wash of a new item, usually in a hurry, before some event. One rule is enough to remember the most important thing: water temperature should be in the range of 20 to 30°C, never above 30°C for unstabilized classical viscose.
Above this threshold, water intensifies fiber swelling, which directly increases the risk of shrinkage. Warmer water also accelerates color fading, so the garment may come out of the first wash not only smaller but also discolored.
Below you will find not just the temperature, but the full picture: why viscose reacts so strongly to water, how to wash it in the machine and by hand step by step, which mistakes to avoid, and when it is safer to hand the item to a laundry instead of risking a wash at home.
Why viscose reacts so strongly to water
the fiber structure that explains its fragility when wet
Viscose is a cellulose fiber made from processed wood pulp, which is why it is sometimes called artificial silk. Chemically it is close to cotton and linen, but its internal structure is far looser and less ordered, which makes it much more vulnerable to water.
When a viscose fiber comes into contact with water, water molecules penetrate between the cellulose chains and weaken the bonds that hold the fiber structure together. The fiber swells, and its tensile strength drops by as much as 50 to 70% compared to the dry state. This is the opposite of what happens with cotton, which is actually stronger when wet, not weaker. That is exactly why wet viscose needs far gentler handling than it might seem at first glance.
Viscose dry versus wet
Drops by 50 to 70% in the wet state compared to dry
Very high, the fiber soaks up water and swells quickly
Low, the fabric stretches easily and loses its shape under its own weight
Increases with water temperature and washing intensity
Rules for washing in the machine
temperature, program, and spin matched to a sensitive fiber
Temperature and Program
Wash at 20 to 30°C, on a delicate cycle or one intended for wool and silk. Limit spinning to a maximum of 400 to 600 revolutions per minute, and shorten the entire cycle to 30 to 45 minutes if your machine allows it.
Detergent
Choose liquid detergent with a pH in the range of 6 to 8. Avoid optical brighteners and detergents with high cellulase enzyme content, which can dull the fiber surface and cause pilling.
Load and Spinning
Do not overload the drum: filling no more than 50% of the washer's capacity limits friction between wet, weakened fibers. Hand wringing and twisting of fabric is prohibited without exception.
These rules have specific physical justification, not a random set of recommendations. A smaller washer load means less mechanical friction between wet, weakened fibers, and it is precisely this friction that is responsible for pilling and wear-through.
A shortened washing time serves a similar purpose: it limits the time the fabric spends in contact with water, and thus the degree of fiber swelling. The shorter viscose remains wet under the mechanical action of the drum, the lower the risk of permanent deformation.
Low spin speed works on the same principle: a strong spin pulls on wet, weakened fibers and locks in stretched seams that can no longer be ironed back into their original shape.
Hand washing step by step
when the label calls for hand washing only
- 1
Soak in lukewarm water
Dissolve the detergent in water at 20 to 30°C before putting the fabric in. Sprinkling powder directly onto the material risks a local discoloration.
- 2
Gently squeeze the fabric
Press the material with your hands, pushing water through the fiber. Never wring or rub the fabric against itself, as that accelerates pilling.
- 3
Rinse several times
Rinse in clean water at the same temperature until it stops foaming. A sudden change in water temperature between washing and rinsing encourages shrinkage.
- 4
Remove excess water with a towel
Wrap the wet fabric in a terry towel and lightly press the entire surface, without pressing into specific spots. Dry flat, away from sunlight and radiators.
Never do this
Chlorine, that is, sodium hypochlorite, is absolutely prohibited on viscose. It is a strong oxidizer that degrades cellulose chains, leading to yellowing of the fabric and, in extreme cases, to the formation of holes.
Common mistakes when washing viscose
Tumble drying is one of the most common mistakes with viscose. Hot air and friction against the drum act on the weakened wet fiber just as destructively as water that is too hot. A second typical mistake is hanging wet viscose on a hanger. Wet fabric has low strength and stretches unevenly under its own weight, especially around the shoulders and neckline. Always dry viscose laid out flat.
Washing viscose at a glance
Do
- Wash at 20 to 30°C, on a delicate cycle or one for wool and silk
- Limit spinning to a maximum of 400 to 600 revolutions per minute
- Dry laid out flat, away from sunlight and radiators
- Check the label before the first wash, some viscose requires hand washing only
Don't
- Do not use chlorine or optical brighteners
- Do not wring or twist the wet fabric
- Do not tumble dry
- Do not hang wet viscose on a hanger, it stretches under its own weight
When to hand viscose to a laundry
If the garment has decorative elements, a lining made of a different material, uncertain colorfastness, or you simply care about it too much to risk a home wash, handing it to a laundry is the more sensible choice. Professional washing matches temperature, detergent, and drying method to the specific fabric instead of relying on universal rules from a label.
Now you know the theory. Practice can be less forgiving.
If you would rather not risk your favourite piece, leave it to the specialists at Gorące Żelazko laundry in Lublin.
Frequently asked questions
Yes, as long as you set the temperature to 20 to 30°C, use a delicate or wool-silk cycle, and limit spin to a maximum of 400 to 600 revolutions per minute. It's also worth not overloading the drum and never hand-wringing the fabric.
Cellulose fiber swells in contact with water, and water molecules weaken the internal bonds of the fiber structure. As a result, wet viscose loses as much as 50 to 70% of its tensile strength compared to dry, unlike cotton, which is stronger when wet.
No, never. Chlorine degrades viscose cellulose chains, leading to yellowing and, in extreme cases, to holes in the fabric.
No. Hot air and mechanical friction against the dryer drum act on the wet, weakened viscose fiber just as destructively as washing at too high a temperature. Always dry viscose laid out flat, away from sunlight and heat sources.
Wet viscose has low strength and elasticity, so it stretches unevenly under its own weight, especially around the shoulders. The result can be a permanently deformed garment shape that ironing can no longer fix.
About the author
Małgorzata Małecka
Owner of the Gorące Żelazko laundry
Małgorzata Małecka runs the Gorące Żelazko laundry in Lublin. Together with her team, she makes sure customers' clothes, shoes and fabrics come back clean and in the best possible condition.
