Cool! Jumper that stops you overheating

IT Is one of life’s frustrations, putting on a jumper only to get too hot and have to take it off again.

But scientists may now have an answer – a self-cooling pullover.

Researchers have created a material which heats up when someone gets too cold. But it also detects when they are warm enough and releases heat to maintain the perfect temperature. The clothing is made out of regular wool but coated with a super- thin layer of conductive metal. Its creators claim this is better at altering the body’s temperature than breathable sportswear on the market now.

Professor Min Ouyang, of the University of Maryland, said: ‘This material was created with the idea of making sure someone can remain comfortable.’

Researchers coated wool in ‘nanotubes’ which are a millionth as thin as a human hair. The fabric underneath detects if someone is getting slightly warm, as their skin becomes damp with sweat. This causes the fabric fibres to pull closer together, creating strong electromagnetic coupling to enhance infrared radiation that expels heat from the body.

But if someone starts feeling a bit chilly again, the material will expand, with the metal pulling in warmth from the air outside.