TECHNICAL WATERPROOF FABRICS

Exciting advances in textile design are leading to drier, warmer and lighter marine clothing. Sam Fortescue explains the benefits, and the science

- Sam Fortescue

Not all that long ago the last word in marine waterproofing was sailcloth coated with tar and some stout woollens. With no more protection than that, fishermen, sailors and explorers achieved the most astonishing feats of endurance in cripplingly bad weather conditions. Frankly put, extreme clothing was pretty rubbish.

As late as the 1964 Tokyo Olympics, sailors were still competing in flannel trousers and Guernseys. However, British sailor Keith Musto, who won silver at the games, was soon to upend all that by bringing in modern technical fabrics for the first time. The company he founded, Musto, is still at the cutting edge today, but there are now a host of competing high-quality manufacturers, from Henri Lloyd to Helly Hansen. And they are all trying to find the same elusive sweet spot where waterproofness, breathability and comfort meet.

Musto famously uses Gore-Tex in its high performance MPX and HPX wet weather gear, as does Canadian brand Mustang Survival. But what does that really mean? Well, Gore-Tex is the ‘secret sauce’ – the vanishingly thin membrane which makes the garment waterproof and breathable. Sandwiched between the inner mesh and hard-wearing outer layers of a jacket or trousers, it is actually made of polytetrafluoroethylene (aka Teflon or plumber’s tape), which has been stretched so that billions of tiny pores rupture the surface. This leaves the material minutely perforated, or micro-porous.

So, when you’re wearing a Gore-Tex jacket, you’re really wearing a very, very fine filter.