Bloomberg published an article today talking about "climate-friendly apparel startups." One of the companies is a British one called Techniche International. Their main target market seems to be construction workers and supposedly their clothes can lower skin temperatures by as much as 8C.
The way they work is through evaporative cooling. Workers start their day by soaking their "StayQool" suits. Once activated, the uniforms will then consistently remove heat from the body for up to 7 hours. (I am curious if it's akin to putting on somebody else's wet life jacket.)
This is an obviously useful thing in a place like Qatar -- the example that Bloomberg gives and where summer temperatures can hit 50C. But the overall trendline suggests this is going to be a growing market. Especially if the tech works really well, it doesn't feel like you're putting on a wet life jacket, and if there are demonstrable productivity improvements.
According to Bloomberg, the company did £150,000 of revenue in 2014 and £7 million last year.