Roadside signage that indicates to the road user that the outside temperature is such that there is a risk of ice on the road

摘要

A permanent roadside sign capable of displaying a warning when the temperature drops to a specified level, for example by way of chemical components. The warning may be wording such as Warning: Ice or other suitable message or symbol indicating the possibility of a slippery road surface such as black ice and/or snow. The device may display advertisements or other information when inactive. The temperature measuring may be carried out by a thermometer comprising a flexible or rigid strip of microencapsulated temperature responsive liquid crystal material, or thermochromic liquid crystals.