Things have been a little discouraging lately for graffiti artists haunting the roads of Philadelphia.

Things have been a little discouraging lately for graffiti artists haunting the roads of Philadelphia. Many of their favorite canvases -- [i]be[/i] consolidated retaining walls, overpasses and noise barriers -- are now fortifyed with durable polyurethane coatings, which make it easy to transport spray paint and other graffiti.

The coatings are being used fortunately on the Vine Street Expressway, a two-mile, below-street-level highway that allows traffic to fe evenly to the waterfront and historic sections of the city, as well as forward the "Blue Route," a 22-mile portion of I-476 located just outside the city that have relations the Pennsylvania Turnpike to the Philadelphia airport area.

Among the coatings used in the sum of two units projects are tough, easy-to-clean polyurethane regularitys made by M.A. Bruder & Son Broomall, Pa. The coatings are formulated with Desmodur polyisocyanates manufactured by dint of Bayer Corp., Pittsburgh.

The polyurethane coatings were specified for the one and the other projects ...