Why synthetic socks build static
Short answer: Nylon and polyester absorb almost no moisture. Without a thin film of water, charge cannot be led away, and every movement in the shoe builds up more of it. That is why synthetic socks give static more often than socks made from fibres that hold a little moisture.
Fibres without water do not conduct
Cellulose fibres always contain a little water and therefore lead charge away slowly. Synthetic fibres are almost dry and behave like insulators. The charge stays where it arose and builds with every movement until it finally discharges with a small crackle.
What water does to a fibre
A thin layer of water on the surface is enough to carry electric charge away slowly. Fibres that take up a little moisture from the air and from the skin have this layer with them all day. Fibres that do not stay dry, however humid the air is.
The shoe is a charging machine
The foot moves in the shoe thousands of times a day. Every movement rubs sock against sole and sock against foot, and every rub can move a little charge. See bamboo tennis socks for men, which are worn in shoes where things rub all day.
Sole and sock are not alike
The charge depends on which materials rub against each other. A rubber sole and a synthetic sock are not the same as leather and cotton, so the result differs from shoe to shoe. The floor also plays a part, because that is where the charge finally has to go.
Why it crackles when you take the sock off
The charge has built up all day and discharges at once when the fabric leaves the skin. Then you feel the crackle, and you can see the sock cling to the leg. It is the same mechanism as with a jumper you pull off. See bamboo underwear for men.
Dry air strengthens it
In winter the air is cold and dry, and indoors it gets even drier when the heating is on. Then there is no moisture to help the charge away. That is why static socks are mostly a winter issue and rarely cause trouble on a humid summer day.
Is static harmful
No, but it is unpleasant and draws dust, lint and hair to the fabric. A sock with static can cling to trouser legs or creep up the leg. The charge is small and harmless, but it can feel irritating over a long day in the shoe.
What to do about static socks
Raise the humidity, avoid over-drying and choose fibres that hold a little moisture. Avoid the tumble dryer if socks become very charged. A few drops of water on your hands, stroked over the sock, can also help for a moment. See bamboo underpants for men.
Do cellulose fibres never give static
Rarely. In very dry air it can happen, but to a much smaller degree than with pure synthetic fibres. That is due to the small amount of moisture the fibres carry themselves. Blends can land somewhere in between, depending on the share of synthetic fibres.
Frequently asked questions
Do cellulose fibres never give static?
Rarely. In very dry air it can happen, but to a much smaller degree than with pure synthetic fibres, because cellulose fibres always carry a little moisture and therefore lead charge away slowly.
Is static harmful?
No, but it is unpleasant and draws dust to the fabric. The charge is small and harmless, but it can make socks irritating to wear, because they cling to the leg through a long day.
What do I do about static socks?
Raise the humidity, avoid over-drying and choose fibres that hold a little moisture. Avoid the tumble dryer if socks become very charged, and moisten your hands lightly if the sock clings.
See our range of men's bamboo socks.
