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A non-stick surface that can repel liquids has been developed using tiny 'umbrellas' to increase the surface area of a structure.

Previously, liquid-repellent waterproof surfaces relied on plastic coatings such as Teflon, which degrade at higher temperatures.

However the new method makes the surface of a material 'rough' in order to prevent water resting on the surface - and could have a variety of uses from surgery to electronic circuits.

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University of California scientists have developed a super-repellent material. It uses 'umbrellas' a fifth the width of human hair to increase surface area. This prevents a variety of liquids including water, methanol and solvents like FC-72 (all shown above) from sticking to the surface

The research, published in the journal Science, was carried out by a team of scientists at the University of California.

Their method involves etching surfaces, in this case silica, with tiny structures to make them resemble a 'bed of nails'.

Each nail head measures a mere 20 micrometers across, which is about one fifth the width of a human hair, and limits the surface area that liquids can contact with.

This means that when a liquid comes into contact with the surface, instead of spreading out, it remains as a droplet - a property known as 'superomniphobic'.

Each head of the nails is also undercut, resembling an umbrella, which stops liquid from seeping into the gaps between them.

On this engineered surface, even completely wetting liquids roll around like a ball and slide right off when the surface is tilted. 

What what's more, as the surfaces don't use a coating they can survive high temperatures - up to 1,000°C (1,830°F).

And the material isn't just repellent to water but also liquids with a much lower surface tension, known as fluorinated solvents.

Of the numerous touted uses, the surface could be used for medical instruments so that blood and other fluids do not adhere to them.

It could also be used in electronic circuits to prevent them being vulnerable to wet weather.

'Usually artificial surfaces repel water because of the chemical composition of the material, but in our case, the repulsion is completely by mechanical means,' study co-author Dr Chang-Jin Kim told Live Science.

The effect can also be used on other materials such as mental, tungsten and plastic.

For now, though, the process to make the structures is quite impressive, although the researchers said the technique could be mass-produced.

The researchers said it could be capable of lasting a long time in an outdoor environment, such as on buildings or vehicles, because its repelling properties would not degrade from ultraviolet light exposure and extreme temperatures.

And it could improve biomedical devices because its repelling properties would not degrade because of damage from biofluids.

New material designed to be superrepellent to liquid droplets

Methanol is seen here beading on the hydrophobic material (right) as compared to Teflon on the left. 'Usually artificial surfaces repel water because of the chemical composition of the material, but in our case, the repulsion is completely by mechanical means,' said study co-author Dr Chang-Jin Kim

Of the numerous touted uses, the surface could be used for medical instruments so that blood and other fluids do not adhere to them. It could also be used in electronic circuits to prevent them being vulnerable to wet weather, or perhaps even in car windows (stock image shown) to prevent water sticking to them