Nikwax Analogy - Technology

Technology

The key to the system is the inner "pump" layer which is designed to move moisture from one face to the other by means of capillary depression (a surface tension effect causing fluid to move along a tube in the direction of increasing diameter). Combined with an outer layer that slows down incoming rain and wind, the "pump" layer is able to push water away from the wearer at a rate which should keep them dry. Since both components of the system are, by themselves, porous and air-permeable, the Analogy system is considerably more breathable than waterproofs relying on a non-porous layer. Unlike most "waterproof breathable" fabrics, Analogy can pass out liquid water as well as vapour.

Unlike a conventional waterproof fabric, Analogy would fail a hydrostatic head test (if used to seal the bottom of a tube containing water, only a very short column could be supported). However, like fur, Analogy causes water to flow away from the body of the wearer and with water typically moving out faster than it arrives the garment is effectively waterproof from the wearer's point of view. Without a formal seal required, Analogy does not need the taped seams required by e.g. Gore-Tex rain-wear, and punctures in the outer layer do not compromise the action of the twin-component design.

The "pump" layer and the shell fabric both rely on a Durable Water Repellent treatment; this treatment in combination with the fabric structure of the "pump" layer creates the capillary depression effect that allows water to be driven away from the wearer. In common with other waterproof garment technologies, this water repellent treatment must be maintained in order to remain effective.