The science of pee back paint: It is inspired by nature

The basic science behind this unique paint being coated on walls of London to stop public urination comes from nature.

New Delhi,UPDATED: Jan 25, 2023 2:08 PM IST

pee back paint

The Westminster City Council launched the initiative following complaints from residents about public urination. (Photo: India Today/Vani Gupta)

By India Today Web Desk: Badly hit by the menace of public urination, London has a plan to determine people who are ‘stench-ing’ the city’s reputation. Officials in Soho, a London area famous for bars, restaurants, theatres, and other entertainment venues, and known for its bustling nightlife, are coating walls with unique paint.

Why unique?

It splashes back the liquid thrown on it. The anti-pee paint creates a transparent water-repellent layer that splashes back urine when the layer comes in contact with the pee.

The basic science behind this unique paint comes from nature. If you have ever seen a lotus, you might have noticed that water droplets on its leaves do not stick on — they just drop by leaving behind no traces. Science terms this attribute hydrohydrophobic. The same phenomenon has been replicated on the walls in London.

Also Read | London takes aim at public peeing with wall paint that splashes urine back


The paint is mostly made up of acetone and silica with the major constituent being sand. The superhydrophobic coating, according to its manufacturers, keeps objects dry and is capable of repelling almost every liquid that is thrown on it. While the company does not disclose the unique chemical that does the trick, experts believe it could be a polymer that acts as an additive.

The coating is to be applied in two stages with the first stage acting as a base primer. (Photo: AFP)

Ultra-Ever Dry, which manufactures the paint, said that it uses an omniphobic technology to coat an object and create surface chemistry and texture with patterns of geometric shapes that have peaks or high points. These high points repel water, some oils, wet concrete, and other liquids.

A 2015 study revealed that the lotus effect is attributed to a surface structure that is covered with needle-shaped wax tubes, and the remaining surface allows invasion of the water droplet and enlarges the interaction with water. The paint creates those high points.

Also Read | Isro to get Aditya L-1 payload on Republic Day: It will unravel secrets of the Sun

The coating is to be applied in two stages, with the first stage acting as a base primer. This primer smoothens the surface, making it hydrophobic after which the topcoat is applied. A hydrophobic surface does not allow liquid to stick to it, unlike a hydrophilic surface where water sticks.

The company claims that the paint repels dirty water and some oils, and remains clean and virtually bacteria-free. “When dust, dirt or other molecules accumulate on a superhydrophobic coated surface, a light spray of water or a blast of air grabs the dust and removes it,” the company says in the product description.

A central London district is trying out a novel way to tackle the persistent problem of public urination: so-called anti-pee paint. (Photo: AFP)


The Westminster City Council launched the initiative following complaints from some of Soho’s approximately 3,000 residents, as well as from workers and business operators. The council, which learned about the anti-pee paint after it was used by a local authority in Germany, is aiming to treat walls at 10 Soho hotspots.

“It is very effective — the proof is in the pudding,” local councilor Aicha Less told AFP while demonstrating the innovative invisible paint’s splash-back ability with a bottle of water.

London is, however, not the first city to use this unique recipe of chemicals to deter public urinators. Cologne in Germany was the first to use this paint about seven years ago in 2015.

Also Read | Doomsday clock reset: Humanity is now 90 seconds away from catastrophe


Leave a Reply

Your email address will not be published. Required fields are marked *

Back to top button