Intelligent paint turns roads pink in icy conditions

When temperatures drop, it can be tricky to judge road conditions accurately. Soon, however, some roads could give drivers clear icy warnings by turning themselves pink.

A new temperature-sensitive varnish developed by researchers at French company Eurovia can be applied to road surfaces to warn drivers about dangerous conditions. The technique, still at the testing stage, might help prevent ice-related traffic accidents in future, the researchers say.

The varnish is made of a polymer containing a thermochromic pigment. The same type of coating is already used to make bath thermometers and frozen food packaging that responds to temperature change. However, it is the first time such a coating has been used to monitor road temperatures.

This winter, researchers at Eurovia tested the varnish on roads at different sites in France. They painted squares around a metre across onto the roads and observed how the normally transparent varnish turned dark pink when temperatures dropped below 1 °C. When the temperature rose back above 2 °C, the coating became colourless again.

Source: technology.newscientist.comAdded: 9 April 2008