Cooling Yarns - Why We Clad Ourselves in Synthetics to Perform Better at Sports

Cue our cooling yarn friends, PES and PA

You must have noticed that clothes designed for physical activities are more often than not made from synthetic materials.  As much as we like our viscose pyjamas and cotton jersey tops for every day, when we know things are going to get sweaty, polyester or polyamide (also known as nylon) are the way to go. It’s just what we do, we don’t even question it anymore.

But what is the reason for that?

Synthetic materials are lightweight, soft and available in virtually any colour you can imagine. They don’t retain moisture and irritate skin. Any runners out there? Thigh burns, am I right?

Technology of functional textiles is developing fast and continuously. Did you ever ask yourself why are you supposed to have a separate set of tights for running and a separate one to wear under ski pants? They look the same. Their labels state they’re made of virtually same material composition. What’s the difference?

Stay Cool (Look Hot)

As soon as you start intentionally moving your body your heart rate goes up, your core body temperature rises and you start sweating – how convenient, your body’s very own built-in cooling system! However, the clothes you are wearing provide a layer of insulation, making your body’s cooling system less effective.

Obviously you have to wear something even in when it’s really hot, but how can you find clothes that won’t make you feel even warmer?

In order for your clothes to help you feel cool, few conditions are important:

Clothes must be comfortable, yet well fitting.

Loose clothes provide a layer of air between your skin and fabric and air is a fantastic thermal insulator. Remember, your knitted sweater for cold winter evenings should be extra baggy, while your cycling top should be just right.

The fabric should be thin and airy.

Did you find a polyamide top with mesh inserts under the armpits? That’s the one you want to get. Effective air circulation will keep you feeling cool as drying of sweat is faster.

Do you intend to be active outside in the sun? Choose light colours.

As good as black looks on you, you’re bound to feel hotter in dark clothes than in light ones. Black absorbs energy from light and doesn’t emit as much as white does.

Less related to actual cooling properties, but it’s important to keep other aspects of your personal safety in mind. Are you going for a run on a busy road? Are you hiking a potentially dangerous trail and want to make sure to be seen easily? Consider neon colours. Are you going to be exposed to sun for longer periods of time? Make sure your clothes offer protection against UV radiation (and always, always wear your sunscreen!).

Fabric that can help you feel cool needs to have following properties:

• Wicks moisture quickly and efficiently.
• Enables air circulation.
• Absorbs and dissipates body’s thermal energy.

Even though the way fabric is knitted and how it fits you has the biggest impact on how well it’s going to keep you from overheating, to certain extent, cooling effect can be achieved on yarn level.

Cooling yarn?

How do we as yarn producers achieve cooling properties of our yarns?

Cross section of fibres

At the very beginning of synthetic yarn production, the molten polymer solution is pushed through spinneret holes. This process produces continuous fibres. The shape of the spinneret hole itself determines what the cross section of the fibre will look like.

In order to be able to effectively wick moisture away from you skin, contact area between your skin and your clothing has to be as big as possible, so fibres with flat cross section are a good choice. If, on the other hand, you want your garment to keep you as warm as possible, hollow cross section of fibre is a great idea.

(Do you see now why wearing running tights under skiing pants is less than ideal choice?)

Heat conducting minerals

Some minerals and ceramic particles have the ability to conduct heat. Minerals such as graphene, silver and different oxides have good heat conducting abilities, which really means they are better at transferring thermal energy from the surface of your skin between its own atoms. This property makes glass feel colder to touch than wood.

Using special technology, yarn producers can embed millions of tiny heat conducting mineral particles to the surface of cooling yarn, keeping you fresh on a micro level.

Moisture absorbing properties of fibres

Another way clothes can help you feel cooler is by helping drying your sweat as fast as possible. The faster the drying, the better the cooling effect. Which is why the fibres on your skin need to be able to absorb as much water as possible as quickly as possible. In order to achieve that we need as many little channels for water to travel through the fabric as possible. Every little yarn your sports top is knitted from constitutes of a certain number of fibres. Each of these fibres represents a little channel that helps water travel away from your skin, transport it across a larger surface area and so helps it dry faster.

This is the exact technology that makes microfiber cloths so efficient for wiping up spills (and now you also know how they got their name, you’re welcome!).

Cooling Yarn and The Elusive QMax

If you have ever seen an ad for cooling bedding or activewear, you have most likely also been served a number between 0 and 1, referred to as QMax. Sadly it is most often presented without any additional explanation apart from “whatever we are offering is SO MUCH better than what you already have”, but generally the higher the QMax value, the cooler the material feels to touch.

So what even is QMax value and what does it mean in textile technology?
The QMax value in textiles is a measure of the fabric’s thermal performance, specifically its maximum heat flux or ability to transfer heat. It means the maximum amount of thermal energy that can be transferred through a certain surface area (normally 1 cm²) of fabric in 1 second.

It is important to note that QMax value does not depend solely on properties of the matter it is made of, but also on material thickness, density and even its current moisture content, which means assuming a piece of clothing would perform better simply because of its material composition would be wrong. Even though the properties of yarn play a big role, it is a garment producers’ job to use them as efficiently as possible.

And last but not least, it’s on the person who ends up wearing them to combine them in the smartest possible way.

If you are looking for high quality cooling yarns to help you make your next line of functional activewear, look no further – BETI has you covered! Contact our sales team or check our assortment of available yarns in PES, PA6 and PA6.6.

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