GORE-TEX Membrane
© GOREWEAR
If you are looking for weatherproof, functional clothing and want to pursue your outdoor passion even in wind and rain, you will automatically and usually quite quickly come across the industry leader GORE-TEX (also abbreviated to GTX). Whether it’s demanding trail running over hill and dale, extended trekking tours in the Alps, multi-day climbing excursions in the Peak District or daring mountain bike or road bike expeditions, GORE-TEX is virtually synonymous with being waterproof, windproof and, at the same time, breathable.
Although the brand is well known, many people still don’t know what exactly is behind or in the technology of GORE-TEX and how it works. In this article, we take a look behind the scenes and explain why the brand can shout its confident promise, “GUARANTEED TO KEEP YOU DRY,” from the rooftops.
It all starts with an idea: the development of GORE-TEX
Like many a world-renowned brand, GORE-TEX started as a family business, in a basement, with just an idea. In this case, Bill and Genevieve Gore founded the company that later became the brand in their private home in Newark, Delaware, in 1959 after Bill discovered the synthetic polymer polytetrafluoroethylene (PTFE).
Ten years later, his son Bob Gore developed this discovery further by rapidly pulling PTFE apart (the process is called stretching) to create expanded PTFE (abbreviated to ePTFE). This had many useful properties and just seven years later, in 1976, the first GORE-TEX products were launched, which were waterproof, windproof and breathable even then.
Over time, GORE-TEX has developed more and more solutions, such as various products for seam sealing, as these are usually the weak points when waterproof textiles are processed. As a material manufacturer, GORE-TEX inspects and tests the prototypes of garment manufacturers who use its products.
What is GORE-TEX?
Behind GORE-TEX is W. L. Gore & Associates, Inc., a company that processes fluoropolymers for all kinds of applications, including aviation and medical technology. GORE-TEX is the name of a membrane made of expanded polytetrafluoroethylene (ePTFE) that is used in functional textiles for outdoor, sports and work protection applications. GORE-TEX does not manufacture any clothing itself but rather supplies the basic materials and processing standards that certified clothing manufacturers are allowed to use for their products. These then bear the GORE-TEX seal of approval.
The masterpiece: the GORE-TEX membrane
The GORE-TEX membrane made of ePTFE has an airy, branch-like structure, is wafer-thin (only about 0.01 millimetres thick) and microporous. This means that every square centimetre consists of billions of pores that are 20,000 times smaller than a drop of water. This means that liquid water cannot penetrate the material and simply rolls off. At the same time, the microporous structure ensures that water vapour can escape because the pores are about 700 times larger than a single water molecule.
Even though it is so thin and has tiny pores, the GORE-TEX membrane is windproof because it works like a hedge, its branches catching the impacting wind. However, the membrane alone cannot form a layer of clothing. It is far too thin for that and, despite its inner stability, too susceptible to mechanical influences. To make use of its essential GORE-TEX functions, the membrane is welded like a film with high-performance coatings and outer materials, i.e., laminated.
GORE-TEX technology: how GORE-TEX laminate is made and works
In order to use GORE-TEX membranes in garments, they must be bonded or welded to one or more carrier materials to form a unit, which can then be called a GORE-TEX laminate or GORE-TEX fabric. Appropriate, robust synthetic fibre fabrics made of nylon and/or polyester are usually used for this purpose. In the manufacture of the GORE-TEX laminate, it is of course important that the microporous structure of the membrane is retained and not bonded so that its waterproof and breathable properties are not compromised.
2-layer laminate
Generally, the membrane is permanently bonded to the outer material of the garment, which stabilises the membrane and protects it from mechanical damage from the outside. This 2-layer GORE-TEX® laminate is used in many products – from raincoats to trekking trousers and hiking boots to ski gloves. A loose lining can be incorporated on the inside to increase comfort, but this is simply next to the membrane.
2.5 layer laminate
Many manufacturers also use a durable water-repellent impregnation (DWR), but this is not a layer in the true sense, which is why this material is called 2.5-layer.
3-layer laminate
There is also a 3-layer GORE-TEX® laminate for especially demanding activities. Here the membrane is firmly and permanently bonded as an intermediate layer to the outer material and also to the inner lining, which protects the membrane from damage even better.
Each GORE-TEX laminate can be further processed by garment manufacturers into the desired products. GORE-TEX also makes sure that the seams are sealed with the brand’s own sealing solutions so that water cannot penetrate, especially at these potential weak spots.
What makes the GORE-TEX membrane so special?
The waterproof, windproof and breathable properties of the GORE-TEX membrane, while wonderful, are no longer exceptional in themselves. Meanwhile, other manufacturers can also create microporous membranes from ePTFE through the process of stretching because the chemical compounds and basic processing methods have been established.
The brand’s unique selling point, however, is the durability of products with GORE-TEX membranes over decades. This is achieved through certified processing specifications, rigorous quality standards and product testing. That’s why GORE-TEX has been keeping its “GUARANTEED TO KEEP YOU DRY” promise since 1989. This is emblazoned on the diamond-shaped hangtag on footwear, clothing and equipment as a seal of quality.
The darling of functional outdoor clothing: applications of GORE-TEX membranes
GORE-TEX is suitable for all areas of use where waterproofing and high breathability are important. For this reason, it is particularly popular and successfully used in outdoor clothing such as jackets and trousers, but also in footwear and gloves. These garments often have the abbreviation GTX in their name to make the use of GORE-TEX membranes recognisable in the product name.
However, even GORE-TEX technology can reach its limits during extremely sweat-inducing activities. When you perspire, the drops are similar in size to raindrops and can no longer penetrate the membrane. Then the garment also becomes waterproof from the inside and condensation moisture collects. When this situation occurs, many people mistakenly think that their garment is no longer waterproof. However, this is usually a fallacy. In this case, large vents are needed to allow the rapidly developing body heat to escape more effectively.
Products with GORE-TEX membrane
There are also backpacks and other equipment with GORE-TEX, but if they don’t necessarily have to be breathable, the most is not being made of the precious membrane. Tents with GORE-TEX are also mostly in vain because moisture initially accumulates inside and will condense on the inner wall rather than escape through the membrane due to temperature differences. However, a GORE-TEX membrane can make perfect sense in bivouac tents or bags because the water vapour can escape more quickly as a result of the tight fit.
A revolutionary technology and its development
GORE-TEX has undoubtedly revolutionised the clothing industry and the outdoor world. The bar is high and so are the demands on functional outdoor clothing. But GORE-TEX is not resting on the reputation it has earned over the decades. It continues to research new and better materials that reconcile waterproof and breathable properties even more effectively or deliberately allow one of the properties to dominate for specific uses.
GORE-TEX’s special products compared
Once the basic principle had been researched, the development teams at GORE-TEX did not rest on their laurels but constantly worked on new and further developments that are even better suited to particular areas of use. This has resulted in a whole range of GORE-TEX products that have very specific properties in addition to the usual functions. Examples of these are:
GORE-TEX Paclite
- The membrane is laminated onto lightweight, robust nylon fabrics. This makes the textiles particularly compressible
- The membrane also has an additional protective layer that prevents salt water and insect repellents from altering the membrane
- Particularly suitable for hiking, cycling, everyday life and other activities where pack size and weight are crucial
GORE-TEX Paclite plus
- This clothing has the same advantages as other Paclite products but in addition is particularly hard-wearing, abrasion-resistant and partly equipped with GORE-TEX stretch technology
- Particularly suitable for mountaineering, trekking and fishing
GORE-TEX Pro
- This material is even more robust than usual GORE-TEX products thanks to the triple lamination – even under extreme conditions
- Particularly suitable for extreme challenges, for example, climbing, mountaineering and winter sports
GORE-TEX Shakedry
- The surface has a special water-beading effect so that droplets can simply be shaken off
- This permits the pores of the membrane to be slightly more open on the inside to allow water vapour to escape even more effectively
- There is no additional outer material, which reduces the weight enormously
- Particularly suitable for high-performance activities where rain can be an issue, e.g., running, cycling and hiking, but also for everyday life
GORE-TEX Active
- Clothing with this material is super light and specially tuned for breathability
- Nevertheless, it still fulfils the “GUARANTEED TO KEEP YOU DRY” promise
- Particularly suitable for one-day sporting activities, from cross-country skiing to mountaineering and hiking to running and cycling
The most important GORE-TEX info at a glance
- Material: the GORE-TEX membrane consists of expanded polytetrafluoroethylene (ePTFE), which has a microporous structure
- Waterproof: the millions of pores are 20,000 times smaller than water drops
- Breathable: the pores are 700 times larger than water molecules, thus letting water vapour through
- Windproof: thanks to the hedge principle
- The GORE-TEX membrane is extremely thin but is bonded together with the help of carrier materials and coatings to form a laminate that can be made into functional clothing
- GORE-TEX is durably waterproof and extremely breathable but requires proper care to maintain these functions
Enduringly waterproof with the right care
Even though products with GORE-TEX are advertised as durably waterproof, the laminate can become clogged or lose its breathable properties over time. In order to keep it fresh, GORE-TEX products should therefore be properly cared for so that you can enjoy them for many years to come. For this reason, we have compiled care tips and washing instructions for GORE-TEX garments in general and specifically for footwear, which you can find here and here .