Nikwax Analogy

Last updated

Nikwax Analogy is a two-component fabric system for weatherproof clothing based on "biomimicry" of fur (the system was originally called "Nikwax Biological Analogy").

Contents

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 [1] (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.

Characteristics

A factor of the two-fabric system is that it inevitably adds insulation, due to the requirement of the inner "pump" liner: being a fur substitute with a definite and designed structure it traps air as well as channeling water, which has an insulating effect. While this can be useful in cooler conditions it is less suitable for higher temperature and/or high activity conditions where overheating is more of a problem than an alternative which provides less insulation. Adding venting features to garments helps address this problem, but it is only a partial solution.

Clothes made from Analogy can also be heavy compared to many examples of waterproof "hard shells" (but not necessarily to the combined weight of these and an insulating layer) and are relatively expensive. [2] Though the veracity of this may depend on the system it's compared to, as for many applications it means that fewer overall items need to be carried, potentially reducing the total garment count and expenditure. The weight issue has been addressed by the production of Nikwax Analogy Light which uses a lighter windproof outer with the same Pump Liner fabric, resulting in garments that are 19-20% lighter than the same style made in standard Analogy fabric. Examples of these are the Velez Adventure Light Smock, the Quito Jacket, the Vista Jacket and the Velez Adventure Trousers.

The high "breathability" of the system makes it more suitable than conventional "hard shell" waterproofs for general use, as opposed to only being used in foul weather. This can offset the extra weight of the system, as extra garments for different conditions are less likely to be required.

Clothes and Market

The main user of Analogy is Nikwax's sister company Páramo with some other small specialist suppliers also producing garments from it. While Analogy clothes have a dedicated following among UK mountaineers, Paramo distribution and marketing to the mass market and outside the UK seems to be extremely limited. [3]

See also

Waterproof fabric

Related Research Articles

Wetsuit Garment for thermal insulation from water

A wetsuit is a garment worn to provide thermal protection while wet. It is usually made of foamed neoprene, and is worn by surfers, divers, windsurfers, canoeists, and others engaged in water sports and other activities in or on water. Its purpose is to provide thermal insulation and protection from abrasion, ultraviolet exposure, and stings from marine organisms. It also contributes extra buoyancy. The insulation properties of neoprene foam depend mainly on bubbles of gas enclosed within the material, which reduce its ability to conduct heat. The bubbles also give the wetsuit a low density, providing buoyancy in water.

Sleeping bag Insulated covering for a person

A sleeping bag is an insulated covering for a person, essentially a lightweight quilt that can be closed with a zipper or similar means to form a tube, which functions as lightweight, portable bedding in situations where a person is sleeping outdoors. Its primary purpose is to provide warmth and thermal insulation through its synthetic or down insulation. It also typically has a water-resistant or water-repellent cover that protects, to some extent, against wind chill and light precipitation, but a tent is usually used in addition to a sleeping bag, as it performs those functions better. The bottom surface also provides some cushioning, but a sleeping pad or camp cot is usually used in addition for that purpose. The bottom surface of a sleeping bag may be moderately water repellent, but a plastic tarp or groundsheet is often used to protect against moist ground.

Gore-Tex Trademark for a waterproof, breathable fabric

Gore-Tex is a waterproof, breathable fabric membrane and registered trademark of W. L. Gore & Associates. Invented in 1969, Gore-Tex can repel liquid water while allowing water vapor to pass through and is designed to be a lightweight, waterproof fabric for all-weather use. It is composed of stretched polytetrafluoroethylene (PTFE), which is more commonly known by the generic trademark Teflon. The material is formally known as the generic term expanded PTFE (ePTFE).

Dry suit Watertight clothing that seals the wearer from cold and hazardous liquids

A dry suit or drysuit provides the wearer with environmental protection by way of thermal insulation and exclusion of water, and is worn by divers, boaters, water sports enthusiasts, and others who work or play in or near cold or contaminated water. A dry suit normally protects the whole body except the head, hands, and possibly the feet. In hazmat configurations, however, all of these are covered as well.

Raincoat Waterproof coat

A raincoat is a waterproof or water-resistant garment worn on the upper body to shield the wearer from rain. The term rain jacket is sometimes used to refer to raincoats with long sleeves that are waist-length. A rain jacket may be combined with a pair of rain pants to make a rainsuit. Rain clothing may also be in one piece, like a boilersuit. Raincoats, like rain ponchos, offer the wearer hands-free protection from the rain and elements; unlike the umbrella.

Diving suit Garment or device designed to protect a diver from the underwater environment

A diving suit is a garment or device designed to protect a diver from the underwater environment. A diving suit may also incorporate a breathing gas supply. but in most cases the term applies only to the environmental protective covering worn by the diver. The breathing gas supply is usually referred to separately. There is no generic term for the combination of suit and breathing apparatus alone. It is generally referred to as diving equipment or dive gear along with any other equipment necessary for the dive.

Extreme cold weather clothing Type of clothing

Extreme cold weather clothing refers to clothing for arctic or mountainous areas. Its primary function is to trap air as an insulator to prevent heat loss from the wearer's body. Secondary and necessary is to conduct water vapor away from the body to keep the insulating layers dry. A shell keeps the wind from disturbing the still air in the insulating layers. In warmer conditions, the shell protects from water intrusion.

Ski suit Clothing for skiing

A ski suit is a suit made to be worn over the rest of the clothes when skiing or snowboarding. A ski suit made for more casual winter wear outdoors may also be called a snowsuit [ˈsnoʊˌsut] and are often used by children as everyday outerwear in the winter season. Some suits are specifically made for snowboarders but most are used by either skiers or snowboarders regardless of the style.

Waterproofing Process of making an object or structure waterproof or water-resistant

Waterproofing is the process of making an object or structure waterproof or water-resistant so that it remains relatively unaffected by water or resisting the ingress of water under specified conditions. Such items may be used in wet environments or underwater to specified depths.

Waterproof fabric Textile that resists moisture penetration through its construction, inherent materials or finish

Waterproof fabrics are fabrics that are, inherently, or have been treated to become, resistant to penetration by water and wetting. The term "waterproof" refers to conformance to a governing specification and specific conditions of a laboratory test method. They are usually natural or synthetic fabrics that are laminated or coated with a waterproofing material such as rubber, polyvinyl chloride (PVC), polyurethane (PU), silicone elastomer, fluoropolymers, and wax. Treatment could be either of the fabric during manufacture or of completed products after manufacture, for instance by a waterproofing spray. Examples include the rubberized fabric used in Mackintosh jackets, sauna suits and inflatable boats.

Durable water repellent Fabric finish

Durable water repellent, or DWR, is a coating added to fabrics at the factory to make them water-resistant (hydrophobic). Most factory-applied treatments are fluoropolymer based; these applications are quite thin and not always effective. Durable water repellents are commonly used in conjunction with waterproof breathable fabrics such as Gore-Tex to prevent the outer layer of fabric from becoming saturated with water. This saturation, called 'wetting out,' can reduce the garment's breathability and let water through. As the DWR wears off over time, re-treatment is recommended when necessary. Many spray-on and wash-in products for treatment of non-waterproof garments and re-treatment of proofed garments losing their water-repellency are available.

SympaTex

SympaTex is a type of fabric that is branded as waterproof but "breathable", made or licensed by SympaTex Technologies GmbH a company founded in 1986. The fabric features a waterproof, windproof and breatheable membrane that is laminated to fabrics either on its inner surface or sandwiched between two fabric layers. The latter system offers greater durability, by better protecting the integrity of the SympaTex layer from abrasion to both the outside and the inside of the garment.

Windstopper is a windproof breathable fabric laminate made by W. L. Gore & Associates. One of its most common applications is a lamination with polar fleece, to compensate for fleece's lack of wind resistance.

Sportswear Clothing worn for sport or physical exercise

Sportswear or activewear is clothing, including footwear, worn for sport or physical exercise. Sport-specific clothing is worn for most sports and physical exercise, for practical, comfort or safety reasons.

Layered clothing is a term describing a way of dressing using many garments that are worn on top of each other. Some of the layers have different, largely non-overlapping functions. Using more or fewer layers or replacing one layer but not others, allows for flexible clothing to match the needs of each situation. Two thin layers can be warmer yet lighter than one thick layer, because the air trapped between layers serves as thermal insulation. Layered clothing is particularly relevant in cold climates, where clothing must at the same time transfer moisture, provide warmth, and protect from wind and rain. In a hot and dry climate clothes have very different functional requirements: They must block the radiation from the sun and allow for sufficient air circulation. Therefore, layered clothing in the sense used in this article is largely irrelevant in hot and dry climates. The wicking layer moves the sweat from your skin, where it can be absorbed by the other layers.

Extended Cold Weather Clothing System

The Extended Cold Weather Clothing System is a protective clothing system developed in the 1980s by the United States Army Natick Soldier Research, Development and Engineering Center, Natick, Massachusetts. The first generation ECWCS consisted of parka and trousers plus 20 other individual clothing, handwear, headwear and footwear items which are used in various combinations to meet the cold weather environmental requirements of the US military. The Gen III ECWCS is designed to maintain adequate environmental protection in temperatures ranging between -60 and +40 Fahrenheit

Ventile, is a registered trademark used to brand a special high-quality woven cotton fabric first developed by scientists at the Shirley Institute in Manchester, England. Originally created to overcome a shortage of flax used for fire hoses and water buckets, its properties were also found to be ideal for pilots' immersion suits.

Robert W. Gore American scientist and businessman (1937–2020)

Robert W. Gore was an American engineer and scientist, inventor and businessman. Gore led his family's company, W. L. Gore & Associates, in developing applications of polytetrafluoroethylene (PTFE) ranging from computer cables to medical equipment to the outer layer of space suits. His most significant breakthrough was likely the invention of Gore-Tex, a waterproof and breathable fabric popularly known for its use in sporting and outdoor gear.

Breathability is the ability of a fabric to allow moisture vapor to be transmitted through the material.

Páramo Directional Clothing is a British outdoor clothing company. It was founded by Nick Brown, who also started the Nikwax waterproofing products company.

References

  1. "Capillary Rise and Depression" a useful demonstration of capillary surface tension effects Accessed November 12, 2008.
  2. "Paramo - The People's Verdict" Outdoors Magic gear feature (October 17, 2002). Accessed November 12, 2008.
  3. "Is Paramo the next Gore-Tex?" Outside Online Gearguy question (February 24, 2003). Accessed November 12, 2008.