GORE-TEX: How does the membrane work?

We all know and love this feeling – the feeling of freedom and independence of being out there in nature, nothing is standing in your way or holding you back, you just do what you want to do and follow your heart. But before any expedition there are some organisational things to think about: where is it that you want to go, how advanced is your tour going to be and what is the time schedule? But the weather will mostly remain unpredictable. This guidebook will show you why GORE-TEX products will keep you perfectly prepared for unexpected weather conditions, and will also explain how a GORE-TEX membrane works. 

 

THERE IS NO BAD WEATER, JUST BAD CLOTHES


If you don’t belong to the group of “only-good-weather-nature-lovers”, you know very well that the right attire with the right weather proof profile is a must, so you can enjoy nature to the fullest in any condition: rain, snow or wind. When we talk about reliable and high-quality outdoor apparel, there is no way around one specific functional material: GORE-TEX. But why is that?

 

W.L. Gore & Associates – the company behind GORE-TEX

Wilbert (Bill) L. and Genevieve (Vieve) Gore established the company W.L. Gore & Associates in 1958. They started developing innovations for the market of electronic products, but expanded their product portfolio over the years. Now, their products are also known in the medical, aerospace and textile industry (just to name a few).

1969 was a very important year for the company, because this was the year when Robert (Bob) W. Gore discovered the expanded polytetrafluoroethylene (ePTFE). This new polymer was ideal for new product developments, because it could be individually adapted to the aspirational use.
The expanded PTFE got protected by patent and is distributed under the brand GORETEX.

 

 

GORE-TEX: ONE MATERIAL, ONE TECHNOLOGY, ONE PROMISE


What exactly does GORE-TEX do? We took a closer look at the material and want to point out the benefits:

 

Maintaining the micro-climate

The essential to the feel-good feeling during activities in nature is the micro-climate of our own body. Even though we cannot see it, our body is surrounded by a very thin layer of air, so called “micro-climate”. As the manufacturer Gore explains: we feel the best at about 32 °C, with a 30 % of humidity.
Our micro-climate can easily be influenced by many factors, such as wind, rain or our own motion. This is why GORE-TEX products aspire to protect your micro-climate in the outdoors and therefore offer you wearing comfort during your adventures.

 

Waterproof

Wet clothing redirects your body warmth away from your skin into the free air. During rainy, snowy or foggy conditions Gore-Tex Products are 100 % waterproof. Thanks to the micropores in the material, GORE-TEX products can keep up with a direct water pressure with a water column of at least 28 meters (28,000 mm). Just to give you an idea, a man of average weight sitting on a wet ground could produce a water column of around 2 meters.

 

Windproof

Each stroke of the wind takes away the body warmth from the unprotected areas. This kind of lowering the temperature through convection is called the wind-chill effect. To avoid such cooling down, it is very important to have completely wind-proof materials. The wind impermeability of given material is measured by looking at how many litres of air per square meter per second get through the given material (l/m2/s). The lower this number the higher the protection against wind. All GORE-TEX products fulfil the standard requirement of max. 5 l/m2/s.

 

 

Breathability

Another way of losing your body temperature is through sweat. If moisture accumulating on your skin can’t escape through the layers of your clothes, the garments will get stuck on your skin. This again would have negative impact on your bodies micro-climate. Therefore, it is important to wear materials that allow excessive sweat to wick away. Gore measures the resistance to evaporating heat transfer (RET). All their products have a measuring result somewhere between RET < 13 (particularly breathable) and RET < 3 (extremely breathable) and therefore fulfil the requirement of breathable GORE-TEX products.

 

GUARANTEED TO KEEP YOU DRY™

Gore gives a satisfaction guarantee for all GORE-TEX outdoor apparel: GUARANTEED TO KEEP YOU DRY™. This guaranty promises, that all GORE-TEX textiles will remain waterproof, windproof and breathable during their whole life cycle. Damages because of incorrect use, wrong care or simply wear and tear are excluded from this guarantee. If you are not sure about the right care for GORE-TEX products you’ll find more information our guide GORE-TEX Wash & Care instruction.

 

 

The key of all GORE-TEX products is the membrane


GORE-TEX membrane

The secret behind all of the functional properties of the GORE-TEX products is the unique membrane, which is an extremely thin layer made of extended Polytetrafluoroethylene. If you just look at it with your naked eye, the membrane doesn’t seem to be that strong, but wait till you get a deeper look: The GORE-TEX Membrane consists of more than 1.4 billion pores per square centimetre. These pores are 20,000 times smaller than a drop of water but 700 times bigger than a molecule of evaporated water. This is the reason why evaporated sweat can get through the fabric, but water can’t. In order to preserve the highly functional membrane from chemical substances, such as insecticide sprays or skin creams, it gets additional protection from a protective layer.

 

GORE-TEX laminate

Even though the GORE-TEX membrane is the key to all of the Gore products, it mostly doesn’t work on its own. The membrane in the final product, whether we are talking about shoes, gloves or apparel, is mostly combined and reinforced with other materials. If there is a layer on each side of the membrane, the upper fabric and the lining, we are talking about a 3-layer laminate. In some cases, the membrane gets attached to only one other fabric, this is called a 2-layer laminate.

 

 

GORE-SEAM Tape

The GORE-TEX laminates are used to produce all different kinds of apparel, which is not possible without Seams. Each stitch might be a potential leak, so Gore had to think about a solution to ensure they can hold on to their promise GUARANTEED TO KEEP YOU DRY™. The result is the GORE-SEAM Tape. GORE-SEAM Tape is waterproof and seals each seam in GORE-TEX clothing, shoes and gloves. This step during the production process gets only fulfilled by trained producers in certified factories.

 

gore-seam-tape

 

Product technologies

Every activity sets a different focus, therefore GORE-TEX products as well have to fulfil different requirements, depending on the type of activity, the place and the climate. All these aspects are relevant for the combination of fabrics used for the final product and therefore lead to a variety of GORE-TEX products, each still providing high protection and comfort:

 

GORE-TEX apparel

  • GORE-TEX: ideal for hiking, skiing and everyday life
  • GORE-TEX Active: ideal for highly aerobe activities
  • GORE-TEX PRO: ideal for intensive activities under extreme conditions

GORE-TEX shoes

  • GORE-TEX: ideal for hiking and everyday life
  • GORE-TEX Invisible Fit: ideal for running and everyday life
  • GORE-TEX SURROUND®: ideal for every day and outdoor activities

GORE-TEX gloves

  • GORE-TEX: ideal for winter-, outdoor- and motor sports
  • GORE-TEX Grip: ideal for skiing, snowboarding, freeriding, motor- and outdoor sports

 

Testing at Gore


Every GORE-TEXT product gets tested by Gore:Every GORE-TEXT product gets tested by Gore:

  • Material & system test: Gore constantly tests materials in the laboratory to ensure high quality right from the beginning
  • Human performance test: A climatised chamber and a rain tower simulate different environmental conditions, so Gore can test the products under almost real conditions
  • In the field test: Athletes and experts test each product in its intended range of use
  • Prototype: Every licensee has to sent a prototype of each GORE-TEX product to Gore to let them do the final testing, because only if a product passes in every category, it will then be allowed to get into production and selling

 

 

GORE-TEX products at the Sport Conrad online shop


Sport Conrad has been working with the manufacturer Gore since the early 80’s. Apart from the typical GORE-TEX products such as Jackets or Pants, we also offer waterproof GORE-TEX gloves. Good footwear is definitely one of the most important parts for your outdoor equipment, which can make you feel great, but also ruin your whole experience. At Sport Conrad you can find a large selection of GORE-TEX mountaineering boots, hiking and trekking boots or approach shoes. And for those of you who always have cold feet, we offer a variety of warm winter boots made from functional GORE-TEX materials.

 

If you don’t need full protection from rain and water, you can also browse our online shop for outdoor clothes made of GORE-TEX INFINIUM™. To learn more about this kind of fabric see our blog post “What is GORE-TEX INFINIUM?”.

 

If you take good care of your GORE-TEX products, you can count on their functionality for many walked kilometres, hundreds of cycled roads, numerous trails explored and many mountains conquered. Neither wind nor rain will stop you living and enjoying your best life.

 

Would you like to learn more about GORE-TEX products? Follow these links for further information:

 

→ GORE-TEX Active: The breathing shell

→ GORE-TEX Pro: The high-protective shell

→ GORE-TEX Wash & Care instruction

 

Fotocredit: © www.gore-tex.de