Innovation: Graffiti artists on the skids with non-wettable coating

GRAFFITI artists, your days are numbered. A non-stick coating developed by Dow Chemical Company in Michigan is so non-wettable that spray paint or ink from marker pens can find no purchase on it.

The Dow product - as yet nameless - forms a hard, clear film that can be easily applied to all manner of surfaces. When a marker pen is drawn across it, the ink beads up, leaving most of the surface uncontaminated. The ink can then be washed away with water.

Moreover, the Dow scientists claim they have yet to find a glue that will stick to their product.

Applications of the material are likely to extend well beyond anti-graffiti coatings.

Because hardly anything will stick to it, the coating would be useful in any situation in which a surface needs to be kept free.

Barnacles could be deterred from the hulls of ships, eggs from the surface of frying pans, and grime from the bodies of cars.

The material, which is described in the latest issue of the science journal Nature, has been licensed to 3M Corporation for commercial exploitation.

The spreading of liquid on a surface, or the adhesion of contaminants, results from the surface's relatively high energy. Because they are exposed, surface molecules have a higher energy than those buried within the bulk of the material.

Liquids will spread, or particles of dirt stick if, by covering up the exposed surface molecules, they can reduce the overall energy.

So the ideal non-stick material would have a very low surface energy to start with, ensuring that there is nothing to be gained by covering the surface with other matter.

The polymer Teflon, currently the most familiar non- stick agent, derives its low surface energy from the presence of fluorine atoms at the surface.

But because a film of the polymer is actually porous on the microscopic scale, grime can get down into the cracks and lodge there.

The new material also derives its low-energy surface from fluorine atoms. It consists of short strands of Teflon-like polymer chains, which are attached to a backbone of a different polymer, like the legs of a centipede.

When laid down on a surface, the fluorine-coated chains all line up, pointing up from the surface like an array of bristles, to present a highly orderly, very low-energy outer layer.

The polymer backbone contains appendages, bearing an electrical charge, that make it soluble in water.

Once a film of the material has been deposited from solution on to the surface, a 'cross linking agent' is added to make the film robust.

When cured by moderate heating to between 30 and 120C , this agent forms links between neighbouring polymer chains, joining the whole assembly into a tough network of strands.

As both the film-forming molecules and the cross-linking agent are water-soluble, the coatings can be prepared in a safe and convenient way.

(Photograph omitted)

News
Alan Bennett criticised the lack of fairness in British society encapsulated by the private school system
peopleBut he does like Stewart Lee
Sport
David Moyes and Louis van Gaal
football
Arts and Entertainment
Sheridan Smith as Cilla Black and Ed Stoppard as her manager Brian Epstein
tvCilla Episode 2 review: Grit under the glamour in part two of biopic series starring Sheridan Smith
News
i100
PROMOTED VIDEO
Life and Style
Vote with your wallet: the app can help shoppers feel more informed about items on sale
lifeNew app reveals political leanings of food companies
Arts and Entertainment
The cover of Dark Side of the Moon
musicCan 'The Endless River' carry on the tradition? See for yourself
Sport
New Zealand fly-half Aaron Cruden pictured in The Zookeeper's Son on a late-night drinking session
rugby
Arts and Entertainment
Worldwide ticket sales for The Lion King musical surpassed $6.2bn ($3.8bn) this summer
tvMusical is biggest grossing show or film in history
Voices
A new app has been launched that enables people to have a cuddle from a stranger
voicesMaybe the new app will make it more normal to reach out to strangers
Arts and Entertainment
Salmond told a Scottish television chat show in 2001that he would also sit in front of a mirror and say things like,
tvCelebrity Trekkies from Alex Salmond to Barack Obama
News
ebooksAn unforgettable anthology of contemporary reportage
Life and Style
food + drink
News
Rob Merrick's Lobby Journalists were playing Ed Balls' Labour Party MPs. The match is an annual event which takes place ahead of the opening of the party conference
newsRob Merrick insistes 'Ed will be hurting much more than me'
News
A cabin crew member photographed the devastation after one flight
news
Life and Style
Carol O'Brien, whose son Rob suffered many years of depression
healthOne mother's story of how London charity Maytree helped her son with his depression
Life and Style
People walk through Autumn leaves in St James's Park yesterday
tech
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs Money & Business

Trainee / Experienced Recruitment Consultants

£20000 - £25000 per annum + OTE £40,000: SThree: SThree are a global FTSE 250 ...

Trainee Recruitment Consultant - Soho

£20000 - £25000 per annum + OTE £40000: SThree: As a Recruitment Consultant, y...

Trainee Recruitment Consultants - Banking & Finance

£20000 - £25000 per annum + OTE £40,000: SThree: SThree Group have been well e...

Quantitative Risk Manager

Up to £80000: Saxton Leigh: My client, a large commodities broker, is looking ...

Day In a Page

Secret politics of the weekly shop

The politics of the weekly shop

New app reveals political leanings of food companies
Beam me up, Scottie!

Beam me up, Scottie!

Celebrity Trekkies from Alex Salmond to Barack Obama
Beware Wet Paint: The ICA's latest ambitious exhibition

Beware Wet Paint

The ICA's latest ambitious exhibition
Pink Floyd have produced some of rock's greatest ever album covers

Pink Floyd have produced some of rock's greatest ever album covers

Can 'The Endless River' carry on the tradition?
Sanctuary for the suicidal

Sanctuary for the suicidal

One mother's story of how London charity Maytree helped her son with his depression
A roller-coaster tale from the 'voice of a generation'

Not That Kind of Girl:

A roller-coaster tale from 'voice of a generation' Lena Dunham
London is not bedlam or a cradle of vice. In fact it, as much as anywhere, deserves independence

London is not bedlam or a cradle of vice

In fact it, as much as anywhere, deserves independence
Vivienne Westwood 'didn’t want' relationship with Malcolm McLaren

Vivienne Westwood 'didn’t want' relationship with McLaren

Designer 'felt pressured' into going out with Sex Pistols manager
Jourdan Dunn: Model mother

Model mother

Jordan Dunn became one of the best-paid models in the world
Apple still coolest brand – despite U2 PR disaster

Apple still the coolest brand

Despite PR disaster of free U2 album
Scottish referendum: The Yes vote was the love that dared speak its name, but it was not to be

Despite the result, this is the end of the status quo

Boyd Tonkin on the fall-out from the Scottish referendum
Manolo Blahnik: The high priest of heels talks flats, Englishness, and why he loves Mary Beard

Manolo Blahnik: Flats, Englishness, and Mary Beard

The shoe designer who has been dubbed 'the patron saint of the stiletto'
The Beatles biographer reveals exclusive original manuscripts of some of the best pop songs ever written

Scrambled eggs and LSD

Behind The Beatles' lyrics - thanks to Hunter Davis's original manuscript copies
'Normcore' fashion: Blending in is the new standing out in latest catwalk non-trend

'Normcore': Blending in is the new standing out

Just when fashion was in grave danger of running out of trends, it only went and invented the non-trend. Rebecca Gonsalves investigates
Dance’s new leading ladies fight back: How female vocalists are now writing their own hits

New leading ladies of dance fight back

How female vocalists are now writing their own hits