Outdoor Fabrics: Gore-Tex and Beyond
By Tom Watson
"'Twas brillig, and the slithy toves did gyre and gimble in the wabe;
As one enters the realm of petro-chemically-enhanced überfabrics, we begin to pass through a jabberwocky jumble of marketing buzzwords and ultra modern terms for processes and super garments. Each fabric utilizes secret formulas with claims of out performing all competitors on all levels. Some of it is true; some of it is marketing hype - but mostly all have generally raised the bar towards introducing fabric process technology into everyday outdoor wear and gear.
All mimsy were the borogoves, and the mome raths outgrabe."
-From the poem "Jabberwocky" by Lewis Carrol
In order to discuss the latest fabrics being used to create paddling clothing and gear, a few more terms need to be defined:
[Read "Part I: Getting to Know Outdoor Fabrics" for previous terms.]
Durable Water Repellent (DWR)
Basically a characteristic that keeps the exterior of the fabric from allowing water to pass down through the surface and into or through any sub layers. DWR materials typically have a surface that uses the water droplet's surface tension/energy (causes water drops to "bead") to maintain minimal contact with that outermost layer thereby allowing it to flow off rather than penetrate below. Water repellent applications create or maintain a surface that encourages minimal contact whereas dirt, oils and wear affect the surface area allowing the droplets to spread out and eventually seep through more easily. Fabrics designated as "Waterproof" usually refers to the amount of water under pressure it would take to penetrate a surface.
Probably the most-used buzzword in the clothing industry, its intended use is to describe the process by which water vapor is transported or transmitted through layers of fabric to be dispersed (through evaporation) to the outside or via a vented layer of material. Be advised, there is apparently no standardized lab test to measure "breathability" - it's more often based on the manufacturer's own parameters and then promoted according to those findings that support their claims. That doesn't mean the stuff doesn't work or perform well - it's just… marketing! If you see a fabric marked as "WP/BR" it means it's offered as being both water "proof" and 'breathable'.
Laminates vs. Coatings
A 'laminate' is a layer of material applied to a surface (think wallpaper on a wall). Both Gore-Tex™ and eVent (see below) are laminates where a WP/BR membrane is bonded to a sub layer. A coating is usually a WP/BR polyurethane resin solution that is applied directly onto the fibers. Some of the new processes boast better utility by infusing the WP/BR properties into the fibers rather than merely covering the surface like a thin coat of paint.
Coatings can be subdivided:
Microporous coatings are composed of microscopically small channels that are created in the coating by adding a foaming agent that creates gas bubbles - they expand within the coating to form passages large enough to allow water vapor through so the coating can "breathe". Monolithic coatings enable water-attracting fibers to facilitate the movement of moisture through the fabric.
Two other terms that appear often when discussing the attributes of a fabric are hydrophobic - usually continuous pores that allow water vapor to pass through, (a water droplet is too large to pass through whereas the water vapor molecule is much smaller than the passageway); and hydrophilic - a solid membrane that enables water at a molecular level to move through the membrane via solid state diffusion (this has been likened to someone moving along a monkey bars in a playground).
So what does all this have to do with paddling clothing? Well, it's all about how our body's heat loss/retention and hydration processes function. If we get too wet from the cooling effects of sweat, we can both dehydrate and chill down to dangerous levels approaching hypothermia. Getting rid of that excess moisture is dependent on how effectively that water is transferred to the outside via WP/BR materials or simple ventilation. Add to that our individual comfort zones when participating in the outdoor environment, we have several factors to consider when using the right clothing and gear.
One of the factors in all this is humans - we are all different, we react to the same environments differently due to activity levels, physique and metabolism. We need to enable excess moisture to be removed from next to our skin, that moisture needs to escape so our mid layers don't get soaked and ultimately so we don't suffer from too great a loss in body temperature - and we need to find a piece of apparel that will provide all those benefits based on our particular body/activity type…and budget, style preferences, etc.
So, we have the natural fibers that are often combined with synthetics to mutually enhance the performance of each. We have specialized fabrics such as fleece and neoprene that provide insulating layering options and we have the newest fabrics (many under fancy names that are all based on the same foundations with their own "secret" process added).
Raising the bar
The best thing about early forms of Gore-Tex was that it drew attention to this whole world of breathability and waterproofness and what not. Sure it had problems when it was soiled and didn't always keep you completely dry as you may have presumed. Patented in 1976 it quickly became the miracle fabric, the gold standard of the outdoor industry.
Gore-Tex is a basically a porous, monolithic/hydrophilic membrane of a polymer with the same constituency of Teflon™ (a PTFE as defined in Part I). Its structure is that of a series of microscopic nodes attached to fibrils. It is most often applied as an inner layer between protective outer and innermost layers.
Gore-Tex's key attribute is that of being "waterproof"; it enables water to pass through the material through the process of diffusion. One criticism of its function is that the wearer needs to be producing quite a bit of moisture before the fabric "kicks in" and starts diffusing. Also, Gore-Tex uses a PU layer to protect the Gore-Tex from dirt, oil and other pore cloggers. In 2010, Gore introduced Active Shell as an improvement over conventional Gore-Tex. The new process incorporates a no-glue bond to a thinner PU layer that still works on the diffusion principle of water transfer.
- Gore-Tex has nearly 10 billion pores/square inch
- Each pore is 1/20,000th the size of a water drop
- A water molecule is 700 times smaller than a pore opening.
Enter eVent, one of a few new fabric/processes on the market that is claiming new standards for outdoor waterproof and air permeable. Instead of using a protective PU layer to block against oil, dirt, etc., eVent found a way to incorporate that characteristic directly into/onto their PTFE layer.
Other entries in the competition with traditional "breathables" include Polartec Neo Shell claiming to be the most breathable fabric on the market, citing five times the air permeability rates of Gore-Tex and eVent. Apparently part of Polartec's secret technology is that the membrane is not even PTFE, it's PU! Another serious contender is Entrant by Toray. Its claims of breathability put it between Gore-Tex and eVent.
NRS, Columbia, REI and many other purveyors of outdoor apparel feature advanced technology fabrics in their products - each offering their own range of lab stats and benefits. In general, PTFE is more durable than PU, which is why laminates or processes are added as enhancements to offset certain limitations in companion layers.
Rather than go into claims about each new miracle überfabric soon-to-be or currently introduced, know that each manufacturer makes boasts and comparisons of superior features that include secret processes and proprietary lab tests which seem to always show their product coming out on top. Truth seems to be that they are all pretty darn good. Factors of pricing, durability, weight, comfort all affect what process or fabric is available for any particular piece of clothing.
Like other outdoor equipment, clothing is gear; it needs to be maintained for function and safety. These new fabrics aren't Superman's cape, they do suffer from use and abuse. There are some basic maintenance procedures you should follow to optimize the usefulness and life of your garment. Most will have cleaning instructions but general rules are:
- Use regular liquid laundry detergents in warm water, rinse twice
- Do not use fabric softeners or bleach
- Do not dry clean
- Some can be ironed but on "warm" setting, and very carefully
- If water fails to bead, consider applying a surface water repellent
On-water fabric/material for clothing is pretty much use-specific (neoprene for wetsuits and booties, nylons for simple splash jackets, cordura for PFDs, etc.). Higher end paddling gear gets into these super fabrics in limited styles. Once ashore, however, especially once one becomes engaged in other companion activities a change of wardrobe is often in order. That's where these fabric options can open up the field for paddlers.
No matter which specialty fabric you decide upon, it's still proper layering and venting (very important regardless of what super clothing you choose) that will play very important roles in the optimum functioning of that apparel. In many cases a simple waterproof splash jacket or raincoat can work nearly as well with proper ventilation (encouraged by vents, zippers, fit).
The best testing ground will be actual use in the field within your normal activity level in any given environment. Of course, one person's sweat lodge is another's ice box so check around - try to base you choices on practical field use experiences and peer opinions, not just biased lab tests and jabber-hype. Seek out your own comfort/function/utility zone when it comes to choosing your paddling apparel.
Good web sources to delve into more details and opinions on the science and scheming behind these fabrics include:
as well as trademark or textile industry sites and those of popular outdoorwear manufacturers and outlets. And always, be safe and have fun out there!
Tom Watson is an avid sea kayaker and freelance writer. For more of Tom's paddling tips and gear reviews go to his website: www.wavetameradventures.com He has written 2 books, "Kids Gone Paddlin" and "How to Think Like A Survivor" that are available on Amazon.com.