Bill and Vieve set up W. L. Gore & Associates and built up a business based on the use of polytetrafluoroethylene or PTFE, a polymer most recognisable as Teflon, to cover electrical cables. The young Bob, however, was trying to find a way to stretch rods of PTFE to extend its coverage. Although by then the firm had its own premises, he returned to the lab in the family basement to conduct his experiments. Over and again Bob would heat rods of PTFE and then try to gently stretch them only to have them uselessly snap. One night, trying once more, and growing impatient with the lack of success, he heated the rod and then gave it a sharp yank. Instead of snapping, the rod stretched and stretched to more than 800% of its original length. Although amazed at the feat, Bob nevertheless took his discovery to bed and it wasn’t until the next day that he demonstrated it again in front of his father and then to an increasing number of Gore staff. He had created expanded polytetrafluoroethylene – or ePTFE – a microporous structure that was 70 per cent air, and it was waterproof and breathable - the famous properties synonymous with GORE-TEX products. And while, ePTFE is now used in more than 1000 products – from medical devices to guitar strings – the GORE-TEX name became a household term through its use in hiking and outdoor equipment and clothing. It seems fitting that Bob Gore tested many of the early outdoor products himself, having retained a love of the outdoors and hiking first introduced to him when he was still a toddler. The first commercial order for this invention was made 40 years ago this year, which today has resulted in Gore becoming synonymous with the outdoor pursuits sector. The product went on to become a market leader to such an extent that in 1989, the company introduced the GUARANTEED TO KEEP YOU DRY ™ warranty, which places a lifetime guarantee on all GORE-TEX product to either repair it, replace it or refund the purchase price if the consumer isn’t happy. Throughout the past 40 years, the company has been at the forefront of innovation, which includes the introduction of GORE-TEX Paclite in the last 1990s. This opened the door to extremely lightweight and small, packable functional outerwear, as the weight per square metre of fabric was reduced from 160g to less than 100g. To cater for those who find themselves in the most rugged of environments GORE-TEX Pro was introduced in 2006, with the light & fast GORE-TEX Active and GORE-TEX Active with Permanent Beading Surface – the company’s most breathable ever GORE-TEX products – following in later years. Forty years on, whether it’s for running or cycling, skiing or hill walking, Gore is still proving that it’s innovating in all sectors of the outdoors activities market, continuing to build upon the groundwork laid by Bob Gore and his family.

What is your #GORETEX40 moment?

In the last 40 years, have you experienced a fantastic adventure with your GORE-TEX gear? Share it with us! Use the hashtag #GORETEX40 between October and December 2016 and upload your best photo to Facebook, Twitter or Instagram. Every week we will choose one random winner from the posts and award the participant a pair of stylish GORE-TEX gloves. The best entry will win the grand prize: A complete winter outfit! Find more details and further information at www.goretex.co.uk/goretex40.