We asked the insider all the questions you have about GORE-TEX® outerwear

From strenuous mountain climbing to peaceful rest, waterproof and breathable outerwear is essential for enjoying the outdoors safely and comfortably. While many material manufacturers are now developing waterproof and breathable materials, GORE-TEX® products are a pioneer and are probably the most well-known material in Japan in the world of outdoor activities, including mountain climbing

GORE-TEX® products have continued to evolve for nearly half a century since their creation, and in recent years, there are many variations of them in response to the diversification of activities. In a market already overflowing with competing products from many manufacturers, I'm sure I'm not the only one who feels that it's getting more difficult every year to find the perfect garment for you

Then, one day in June, I had the rare opportunity to speak directly with someone from Gore, the company that handles GORE-TEX® technology. I had always had questions that would turn most people off: "Which is stronger, the 40D (denier) GORE-TEX® Pro or the 75D GORE-TEX® PACLITE®?" So I couldn't miss this opportunity

The person who answered our questions was Natsuko Ichizuka, who is in charge of marketing at Gore Japan. She answered a wide range of questions without a single frown, from product secrets that you may think you know but don't, to tips for beginners to easily choose GORE-TEX® outerwear, and easy-to-understand care and storage methods. So, let's get started! It may be a bit long, but please enjoy!

The two faces of GORE-TEX®: membrane and fabric

- Personally, I've been using GORE-TEX® products for 20 years, but there are still some things I don't fully understand. I understand each of the terms and products, but I'm confused about the relationships between them. So today, I'd like to take a closer look at GORE-TEX® products, so I look forward to hearing from you

Thank you! Let's start with the basics. First of all, what do you think "GORE-TEX®" is?

-Is that... Menburen?

That's certainly true. When you ask, "What is GORE-TEX®?" the first thing that comes to mind is that it is a "membrane." This membrane is a film of fluorine-based resin called "ePTFE," which is made from the mineral "fluorite," and it is the core material of GORE-TEX® products. We call this a membrane in English, and all products that say "GORE-TEX," whether they are shoes or gloves, contain this membrane

- I've been climbing mountains for 20 years, so I've heard this story at least once. This membrane is what they call "water vapor permeable but not water droplets permeable."

This membrane has over 1.4 billion microscopic pores per square centimeter. The size of these pores is 1/20,000th the size of a water droplet, but they are about 700 times larger than a water vapor molecule. This means that "water (rain) and wind cannot pass through, but water vapor (stuffiness) can pass through."

-The GORE-TEX® membrane itself is already waterproof, breathable, and windproof. To put it in extreme terms, if there was clothing made entirely from this, it would be the lightest

You're right in a way. This material alone is waterproof, windproof, breathable, soft, and light. However, the GORE-TEX® membrane itself is so thin, delicate, and easily torn that it's not practical to make clothing out of it. That's why fabric is bonded to the surface or both sides of the membrane to create a practical fabric (GORE-TEX® fabric)

-It's only by combining multiple fabrics that it becomes a practical material

That's right. In fact, this is a little-known fact, but the wide variety of products using GORE-TEX® fabric is the result of a variety of technologies and structures tailored to different uses and purposes, such as the quality, thickness, weaving method, and attachment method of the fabrics attached to the front and back of the membrane

-As a simple example, would you increase the thickness (denier) of the fabrics that are bonded together to improve durability?

That's the simple answer. However, in reality, we consider many more complex and intertwined factors. For example, when it comes to strength, the denier number is merely the thickness of the thread, and is only one factor that determines strength. For example, even with the same denier number, the more densely woven the fabric, the stronger it will be. However, on the other hand, densely woven fabrics will be heavier and, strictly speaking, will also have lower breathability

Why GORE-TEX® products don't publish water resistance and breathability measurements

- Wait a minute, so not only is durability not determined simply by the denier number, but even within the same GORE-TEX® fabric, breathability can vary slightly depending on the thickness and weaving method of the fabric... So does that
mean that, unlike other companies' waterproof and breathable materials, GORE-TEX® products do not disclose figures for water resistance or breathability, and this has something to do with that?

That's one reason. Strictly speaking, all fabrics that use the GORE-TEX® membrane have different performance characteristics. This includes the thickness of the outer fabric and the density of the weave. The tighter the weave, the stronger the fabric, but it also feels crisper and has lower breathability. On the other hand, a looser weave makes it softer and more breathable, but it doesn't increase strength. There are literally thousands of different types of GORE-TEX® fabrics, and theoretically, each has different breathability and other characteristics. In reality, outdoor outerwear is designed by finding a comprehensive balance of these various characteristics to best suit the purpose

-I see……

But that's not all. Breathability performance also varies depending on the state of the fabric and the state of the finished product (garment). For example, seam tape, which is attached to the back of seams for waterproofing, is not breathable. In other words, if a garment has a lot of seam tape, the overall breathability will decrease accordingly. Another factor is pockets. A garment with two pockets will definitely have lower breathability than one. No matter how breathable the fabric used in garments with many pockets, the actual breathability of the garment will be lower. As you can see, various factors are involved in determining the final performance of clothing, so it is not really essential to display the performance of the fabric alone without taking these factors into account

- I didn't know that... I'm starting to wonder if the published specs can even be trusted

Of course, they are certainly useful as reference values, so we're not saying that publishing the figures is entirely wrong. However, Gore always wonders whether publishing them will really benefit users. No matter how precisely we measure, actual usage scenarios will vary, and spec values ​​are only for reference. Nevertheless, releasing figures could lead to them being overestimated as a measure of performance, which is not what we want

―It's true that when you see numbers displayed, it makes you feel like you understand the information. I got used to it and before I knew it, I was comparing the performance of clothing based solely on the numbers

For this reason, we don't publish detailed figures for GORE-TEX® products, and even if we do, we only publish minimum figures such as "more than XX." At the same time, we check every detail to ensure sufficient performance as clothing, such as limiting the area of ​​breathable parts such as pockets and prints at the design stage

The unparalleled quality control of GORE-TEX® products

-This is a good conversation to have, so could you tell us a bit more about the detailed checks that are carried out on GORE-TEX® products?

First of all, GORE-TEX® products require advanced technology and high quality, and can only be made in designated factories with the level of technology and equipment we expect. Performance testing is then carried out on pre-production prototypes made there. While some manufacturers test fabrics, the system of having a material manufacturer test the finished product is probably unique to GORE-TEX® products

- At this point, you're pretty much flawless. What does the actual test involve?

For example, in the case of clothing, we simulate various conditions, such as physically exposing a mannequin to rain while it is wearing the garment, to test whether waterproofness, breathability, etc., meet the standards. In this case, even the water-repellent treatment that is usually applied to the surface of the outer fabric is removed, and the test is conducted on the pure fabric. This is because if the water-repellent treatment is effective, there is a possibility that water may drip off even in places where water would actually accumulate and get wet. It is the policy of GORE-TEX® products to guarantee the waterproofness of clothing to this extent

Waterproofing and water repellency. They are different, and each is important

-Another thing I wanted to ask about, as I haven't seen much written about it anywhere, is the water-repellent properties of clothing. I sometimes see highly water-repellent T-shirts that claim to "repel coffee and wine," but if that's true, then I thought that in the future, if the outer fabric is as water-repellent as possible, then waterproofing might not be necessary

While such products do exist, the reality is that there are no water-repellent treatments that are strong enough and last long enough to be practical

-It's certainly not that easy to make something that can withstand the special environment of the outdoors

First of all, waterproofing and water repellency are different. Water repellency simply repels water that has been applied to the surface of the fabric at the molecular level, so it is weak against pressure. No matter how strong the water repellency becomes, it cannot replace waterproofing

Let's try an experiment that will help you see the difference between waterproof and water-repellent at a glance (photo below)

This is a nylon fabric that has only been treated with a water-repellent coating on the surface. When water is pumped in from below, the water resistance reaches a certain limit at some pressure, and the water leaks out from the bottom to the top. However, because the water-repellent coating is still in effect, you can also see that the water that escapes is repelled (water-repellent) by the surface. In other words, this shows that no matter how water-repellent a fabric is, it cannot prevent water seepage if the water pressure is high

-Is water repellency merely a secondary function for GORE-TEX® fabric?

It's true that water repellency isn't covered by the warranty because it's not one of the three major functions: waterproofing, breathability, and windproofing. However, that doesn't mean that Gore doesn't focus on research and development. If the outer fabric loses its water repellency and absorbs a lot of water, it can't deliver its original breathability, and the garment becomes heavy and uncomfortable. Water repellency is certainly an important factor in the comfort of clothing. However, it's also a complex function that involves many factors, with different fabrics being easier to process. We're striving to make it as good as possible, by changing the formulation depending on the fabric and even developing products like "GORE-TEX® SHAKEDRY™ products" that have water repellency built into the material itself

Next page: Choose your GORE-TEX® outerwear by product class

Choose your GORE-TEX® outerwear from "product classes"

Now that we've learned a lot about GORE-TEX® products, can you clear up any confusion you might have when it comes to choosing a GORE-TEX® product? Is there a simple, foolproof way to choose outerwear?

There's no special secret, but there are some steps you can take to avoid confusion. When choosing GORE-TEX® clothing, we recommend first checking the "product class," which is categorized by use and purpose. You'll see one of three classifications on the large GORE-TEX® tag attached to the clothing: "Product (unbranded)," "Active," or "Pro."

- Can't I just choose based on thickness, weight, or the performance I want?

Of course, that's not entirely wrong. But checking each and every one of those detailed features is, frankly, an extremely difficult task for a beginner. On the other hand, checking this product class is ultimately the same as selecting those features properly and efficiently

-What does that mean?

The performance, functions, and features required for outdoor activities such as mountain climbing, skiing, and running vary widely. Product classes organize the features required for these various uses and categorize them into three broad styles to make it easier to choose. Therefore, by first selecting a class based on your use, you will have selected the basic performance and functions you require

-I see, so class names like Pro product and Active product don't represent any specific technology. On the other hand, what's the difference between the commonly heard names like "PACLITE®" and "C-KNIT™" and product class names?

Terms like "PACLITE® Product Technology" and "GORE® C-KNIT™ Backer Technology" represent the individual "technologies" used in each product class. For example, PACLITE® Product Technology is a technology used in GORE-TEX® products, and is characterized by its lightweight and packable properties. However, it is not used in GORE-TEX® Pro products because it lacks strength. In this way, each physical technology is actually linked to a category according to its characteristics. Of course, this is only current as of now, and we are constantly researching and developing ideas, such as what would be interesting if this and that were combined

--I see, my worries that I've had for years are melting away in an instant. So, what are the specific differences between each class?

Depending on the surrounding environment and the individual's level of activity, GORE-TEX® products are optimized for general outdoor activities in less extreme or stressful environments, GORE-TEX® Pro products for activities involving frequent stops and starts in harsh environments, and GORE-TEX® Active products for activities in less harsh environments but with a sustained high heart rate

Reference: Product class feature comparison table

-Here's a question I actually had: What should I do if I want to choose the more durable product technology, for example 40D GORE-TEX® Pro or 75D PACLITE® product technology?

This is purely a general rule, but strength is determined by several factors. For example, resistance to surface abrasion, or tear strength, which determines how easily the material tears when pulled. So, if you're looking for a winter mountaineering jacket and plan to use a harness, it's better to choose a Pro product over one with PACLITE® Product Technology. The area where the harness comes into contact is particularly susceptible to chafing. The 3-layer Pro product offers superior resistance to abrasion. As mentioned earlier, fabric durability also varies depending on the weave density. Given these points, the key to choosing the best model is to prioritize the product class over minor differences like denier count

-Are there any other points to consider when choosing?

Once you've chosen a product class, the process is basically the same as choosing regular clothing. Even within the same class, there will likely be many subtle differences in clothing form, construction (layers), thickness, weight, and so on, so it's fine to choose the features that best suit your activity and preferences. However, as mentioned earlier, this is something that applies specifically to GORE-TEX® products; each product class may incorporate various technologies that reinforce and enhance its characteristics. Depending on the application, these technologies can often make the garment much easier to use, so be sure to pay attention to them as well

How to care for your GORE-TEX® product

-Finally, I'd like to know how to care for GORE-TEX® clothing. I know I have to wash it, but I'd like to know more about how often to wash it, how to wash it, and other details

First of all, there are two main reasons why you need to wash your GORE-TEX® products. The first is to maintain the water-repellent properties of the surface, which is extremely important in terms of comfort. While the causes of the water-repellent properties of the surface are rare, most cases are caused by dirt. Removing these will restore the water-repellent properties, so it is very important to wash your products frequently to maintain their water-repellent properties

-I see

The other reason is to prevent the water resistance from decreasing due to the seam tape coming off or the membrane itself becoming dirty. The causes of this deterioration are often sweat and sebum, but washing plays an important role in keeping the jacket clean and maintaining its performance for a long time

- This is the first time I've heard that if dirt is left on the garment, it can even lose its waterproof properties. But somehow, GORE-TEX® clothing isn't worn directly on the skin, and I don't imagine washing it very often, so how often is the best time to wash it?

For some reason, many people think this way, but in fact, it's not true at all. Ideally, you should wash your jacket after every wear, even if you don't sweat. We've never heard of any customer inquiries about the jacket deteriorating from over-washing, and in the US, repeated washing tests with the seam tape attached have shown no problems

-Really?! I had no idea it was so important to wash it..

As for how to wash it, you can use regular laundry detergent that doesn't contain bleach or fabric softener, and you should be fine if you put it in a laundry net in your home washing machine, wash it normally, and dry it in the shade (of course, you should check the washing instructions for each piece of clothing)

-Oh, I thought it was all a bit of a hassle to use lukewarm water, use the special detergent sold at mountain equipment stores, or iron it

Of course, the methods we introduce are certainly more effective, but rather than occasionally washing your clothes in a complicated way using expensive detergents, it is more effective in the long run to wash your clothes frequently and multiple times using minimal methods.

-Finally, how should you store it after washing?

Many people leave their jackets unused after returning from the mountains, but in reality, just having them in your backpack allows moisture to penetrate your back. This moisture will cause the jacket to deteriorate, so when you return home, be sure to remove it from the stuff sack, unfold it, and store it in a dry place

summary

The two hours flew by, but for me as an outdoor enthusiast, it was a dream come true, as I was able to answer many questions that I hadn't had the chance to ask directly until now. As a result, the interview didn't cover many basic topics, but basic information can be obtained from a variety of sources, so reading this together with the information will likely lead to a deeper understanding

In fact, the interview covered a wide range of topics, including shoes, gloves, and tents, in addition to what is published here, but we hope to sprinkle the information that we couldn't fit in here into future content

Finally, general information and the latest information about GORE-TEX® can be found on this official page, so please feel free to refer to it

GORE-TEX® Official Website

   

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