Moisture barrier membrane

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A moisture barrier membrane (also called hydro membrane) is a wafer-thin film designed for the production of weather protection clothing, which makes the finished clothing absolutely waterproof, wind and rainproof, i.e. weatherproof, but does not hinder the development and evaporation of body sweat. These membranes cannot be used on their own, but have to be laminated onto the outer fabric, the lining material or warming fleece inserts .

Types of membranes and how they work

Microporous membranes

The micropores of the membranes are 0.02 to 1 µm, much smaller than the smallest water droplets of 100 µm, which is why they cannot penetrate the membranes. Molecules of the body sweat that has evaporated into vapor are normally smaller than 40 × 10-6 µm and can therefore easily pass through the micropores and diffuse outwards using the capillary mechanism. The first membrane of this type was Gore-Tex , developed by WL Gore & Associates and introduced to the market in 1976. The extruded PTFE film is stretched in a defined manner, so that approx. 1.4 billion micropores per cm² are created. Other microporous membranes are Entrant and Porelle, which are manufactured on the basis of polyurethanes by Toray Industries and Porvair, respectively.

Hydrophilic membranes

These membranes are basically pore-free and therefore waterproof and windproof. The breathability is an adsorption-diffusion-desorption process which is accelerated by the hydrogen bonds between water molecules and the functional groups which are incorporated into the molecular chains. An important membrane of this type is Sympatex , which was defined as a brand as early as 1986. It consists of a modified polyester into which polyether groups have been inserted to ensure the hydrophilic properties.

Individual evidence

  1. ↑ Alfons Hofer: Textile and Model Lexicon. Volume 2, L - Z. 7th, completely revised and expanded edition. Deutscher Fachverlag, Frankfurt am Main 1997, ISBN 3-87150-518-8 , pp. 601/602.
  2. ↑ Fabia Denninger, Elke Giese: Textile and Model Lexicon . Vol. 2, LZ.8., Completely revised and expanded edition. Deutscher Fachverlag GmbH, Frankfurt am Main 2006, ISBN 3-87150-848-9 , p. 451.
  3. ↑ A. Richard Horrocks, Subhash C. Annand (Ed.): Handbook of Technical Textiles. Volume 2: Technical Textile Applications. 2nd Edition. Woodhead Publishing, Cambridge 2016, ISBN 978-1-78242-465-9 , p. 31.
  4. ↑ A. Richard Horrocks, Subhash C. Annand (Ed.): Handbook of Technical Textiles. Volume 2: Technical Textile Applications. 2nd Edition. Woodhead Publishing, Cambridge 2016, ISBN 978-1-78242-465-9 , pp. 32/33.