The technique involves spreading an initial layer of a compound which seeps into the pores of the wall and provides a semi-permanent base coat for a second layer.

Once both layers are in place, any paint that comes in contact with the wall will not penetrate the top layer.

The cleaning company can then remove the top layer with hot water in minutes and spray on a new top layer, leaving the wall graffiti free.

The product was developed by Preston based company Green Concept, and if the demo is successful it will be rolled out throughout the city by Clean Close Company environmental engineers.

Clean Close Business Development Manager Alex Fyffe said, “The managing director of Green Concept, Alan Best, laid the groundwork for today’s demo.

“The bottom layer takes 24 hours to set, so it was put up on Monday, followed by the second layer yesterday.

“Alan was out this morning having fun with his spray can, putting various industrial spray paints on the wall.

“His performance was so convincing that someone who works in a unit in Alexander Street came out and asked him what he was doing.

“It was quite a comical scene watching a man in his fifties being told off for spray-painting, but everything was fine once he explained what was going on.”

The Clean Close Company is a not-for-profit business which helps look after properties throughout Dundee and other regeneration areas.

Its activities have resulted in environmental improvements to their neighbourhood, involved local people and partners and provided work and training opportunities for local residents.