Waterproof and Breathable Membrane

Porelle microporous membranes are based on a polyurethane chemistry and are constructed from many small interconnecting micro pores less than 1 µm in diameter.

Porelle microporous membranes are hydrophobic (water hating) and resist the passage of water, even under high pressure. At the same the membrane breathes by allowing sweat in the form of water vapour molecules to pass through the microscopic pores driven by greater heat and the higher density of water vapour molecules from the inside of the garment.

The unique combination of microstructure and polyurethane chemistry ensures that Porelle microporous membranes remain waterproof in use, even after repeated washes or steam sterilisation.

Porelle microporous membranes are available in thickness options: 30, 45 and 55 µm.

porelle dry

Porelle Dry

Porelle Dry is a waterproof and breathable microporous polyurethane membrane that is: light, flexible and durable.

The key feature of the Porelle Dry film technology is its dry feel when used in active apparel applications.

Porelle Dry films are produced by a unique novel coating process which enables the formation of a uniform micro-structure. This ensures consistent waterproofness levels even after multiple washes. Some competitor products have irregular cell structures, with large pores which can inherently lead to failure causing decreases in waterproofness and breathability.

Porelle technology provides a unique solution:

They breathe by absorbing and dissipating sweat through the diffusion of water vapour molecules across the solid structure. Whilst these technologies work, the user can still sometimes find that they feel clammy and uncomfortable.


Waterproof film in Porelle membranes

One of the key functions of membrane technology used in apparel is to ensure that it remains waterproof in use, keeping the user dry and comfortable. However, when we work hard we sweat. If the sweat becomes trapped inside the garment it can create a micro-climate and quickly form a wet layer eventually leaving the user feeling cold. The solution to this is to use membranes that are both waterproof and breathable. TPU and PU films are widely used in apparel applications for this reason. They are generally based on 100% solid hydrophilic film technologies. 

When hydrophilic films are working to dissipate sweat they swell and retain moisture. This is due to chains of chemical groups within the solid structure that attract and hold onto the water vapour molecules. This retention of moisture in the structure changes the nature and character of the film leaving it feeling as though it is actually wet, which can be felt by the user as an uncomfortable, clammy, cold sensation.

Porelle Dry

Porelle Dry is a microporous membrane that breathes by a different mechanism, which allows the character and nature of the film to still feel dry when in use. The membrane is hydrophobic (water hating) and repels water droplets, even under high pressure. At the same time the membrane breathes by allowing the passage of water vapour molecules through interconnecting micro-pores less than 1mm in diameter. In use Porelle Dry is waterproof, breathable and dry feel: offering the optimum in comfort performance.

The science of film technology in the sports and leisure market often relies on waterproofness and breathability test data as a means to define the value of comfort.

To define true comfort requires life trials and user feedback, field test Porelle Dry films and make your own conclusions.

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Porelle Sports and Leisure Divisions

Sports & Leisure membranes from Porelle; lightweight, breathable and highly waterproof for use in activewear apparel and gloves.