Wool as a sustainable functional material

Wool from sheep, goats, and alpacas has been used in textile production for centuries. Who doesn't remember the wool sweaters from grandma's time, often scratchy and shapeless, matted, and not machine washable? So how does one come up with the idea of calling a sheep a high-tech user?

What can wool clothing do?

Wool clothing is a jack of all trades and indispensably valuable for everyday life, travel or sports:

• Woolen clothes do not need to be ironed because they are crease-resistant.
• Wool clothes don’t scratch (anymore).
• Wool clothing absorbs little dirt and odors, so it needs to be washed less often.
• Wool clothing regulates temperature.
• Wool clothing is sweat-wicking with appropriate evaporative cooling.
• Wool is antibacterial.
• Wool clothing can be used in both warm and cold weather, making it ideal for tours with small luggage.
• Wool clothing is made from ecologically sustainable material.

Wool can do so many things that synthetic fibers or other natural fibers like hemp, cotton, or silk can't. Its physical structure and chemical and physical properties explain the advantages of wool as a wonder weapon.

Structure of the wool fiber

The reasons for the natural high-tech material wool lie in its structure: a brief excursion into chemistry and physics.

• Wool fibers consist of a mantle (cuticle) and a core (cortex). The cuticle is a tile-shaped scale layer, the outermost layer of which consists of lipids and is therefore hydrophobic (water-repellent).
• Wool is 97% protein, whose amino acids can bind water. Wool fibers can absorb up to 33% of their own weight in water. This is referred to as hygroscopic behavior.
• A single wool fiber consists of many components arranged in layers. Between these layers, air-filled cavities form. A wool fiber therefore consists of up to 85% air (based on its total volume).
• The protein components of wool fibers are responsible for its mechanical properties: stretchable, flexible, elastic, and tear-resistant. Wool fibers resemble coiled springs and are highly crimped. The finer the wool, the more tightly the wool fibers are intertwined in a spiral pattern.

 

Wool clothing hardly wrinkles

Wool clothing is ideal for traveling: The wool fiber is elastic and always strives to return to its original shape. Therefore, wool clothing is ideal for backpacking or traveling, as it wrinkles little.

Wool clothing hardly scratches these days

Thick sheep's wool sweaters used to itch terribly. Thankfully, that's now a thing of the past. The coarser the sheep's wool, the less crimped it is, and the more of the cuticle layer of the wool fibers lies against the skin. This is the reason for a scratchy sensation. We humans find wool fibers with a diameter of about 25 microns or more unpleasantly scratchy.

Grüezi bag uses Merino wool, a fine wool breed, for its shirts. These wool fibers are on average only 17-19 microns thick (in comparison, a human hair is four times thicker).

Fine wool is highly curved and has a finer scale layer (up to 40 changes of direction per cm), meaning the wool fibers are only slightly exposed to the skin. This is why a wool shirt from Grüezi bag feels soft and comfortable against the skin.

Wool clothing is water-repellent

• The roof-tile-shaped scale layer of a wool fiber and its outermost layer are naturally water-repellent.
• The wool fat lanolin also contributes to the beading effect, as it acts as a protective layer on the fiber and prevents odors and grease from penetrating into the interior of the wool fiber.
• In addition, the highly crimped fibers create a beading effect for water droplets.

We also know this effect from nature, where plants like the lotus plant gave the effect its name: lotus effect.

In earlier times without plastic or even GORE-TEX, people protected themselves from the rain with woolen clothing, such as the well-known felt hat, a tightly woven woolen fabric, or wool jackets, which provide some degree of protection from the rain.

Wool clothing is dirt-repellent and odor-resistant

The outer cuticle layer acts as a natural protective shield against dirt and stains. Additionally, the wool fibers rub against each other during the moisture absorption and release process, preventing dirt from settling in as easily.

The outer layer of the wool fibers, their moisture-absorbing capillary effect and their chemical structure are the reason for the odor-inhibiting properties.

Sweat consists primarily of over 99% water and less than 1% salt ions and proteins. The odor of sweat only develops during the decomposition process on the skin caused by skin bacteria. These bacteria have less chance of settling on the scale-like, water-repellent outer layer, and the rapid wicking of moisture means they lack the moist environment to spread. Sheep's wool even absorbs odors into its fibers, releasing them only during washing.

This makes the garment easy to care for: it needs to be washed less often because it is usually sufficient to air it out in (preferably humid) air.

Wool is insulating in cold and heat

Wool contains a large amount of air volume within its fibers and due to its crimped fibers. Since air is a poor conductor of heat, it perfectly insulates our body heat against cold or hot outside temperatures.

That's why we recommend wool shirts in the summer. While it may sound contradictory at first, they're not only recommended for sun exposure, but also for transitioning into cool, air-conditioned indoor spaces. Best worn in layers, wool shirts are a true secret weapon for maintaining a comfortable temperature on both warm and cold days!

Wool insulates even when wet

Sweaty synthetic functional clothing feels wet and sticky against the skin. Wool can absorb up to a third of its own weight in moisture without causing chills. This is due to the capillary action of the wool fibers:

The fine wool fibers absorb the condensed sweat until they reach saturation, then release the moisture into the outside air. The vapor condenses and releases energy in the form of condensation heat. As long as the wool fibers can absorb moisture, they release heat to the body.

This means that wool creates a good microclimate on the body. Despite sweating, wool feels temperature-regulating on the skin, absorbing moisture without excessive evaporation. The skin feels cooler, fresher, and drier.

To make the most of this effect, the wool sleeping bag, shirt or wool jacket should be as dry as possible beforehand.

A short digression: Why do we sweat?

A person's body temperature must remain as constant as possible and deviate only slightly from its target temperature of 37° Celsius. When overheating occurs, the body attempts to dissipate heat as quickly as possible: through heat loss and sweating. When heat loss to the surrounding air alone is no longer sufficient, sweating comes into play. Up to 4 million sweat glands are located almost everywhere on the body's surface. These can secrete up to 3 liters of sweat per hour during strenuous physical activity, and up to 0.5 liters at night. Sweating has two effects:

• Evaporative cooling occurs on the skin when sweat evaporates into the air. The more evaporation, the more cooling it is for the body.
• The evaporation process draws energy from the environment, making the air cooler. And the cooler it gets directly above the skin, the more heat the body can release back into the environment.

We also know this principle from calf wraps, which lower body temperature through moist compresses. Evaporation works best in low humidity, strong winds, high air temperatures, and strong sunlight.

Wool as insulation material: Sleep naturally and well with lavalan® Alpine wool

Grüezi bag uses filling wool from Alpine sheep for its sleeping bags. DownWool® combines Alpine sheep's wool with down.

The wool sleeping bags are made from wool fleece and supplied by the renowned wool supplier lavalan®. Buyers can track the wool origin "from sheep to shop" using track & trace labels on the sleeping bag (hang tag).

The wool processed by lavalan in the form of a fleece fabric is lightweight, washable, and easy to work with, making it ideal for outdoor use. The wool is brushed, allowing the wool fibers and the wool layer to retain plenty of air and be light and airy. To keep it light and airy yet washable, it is bonded with corn starch (PLA).

lavalan® AlmWolle Fleece

 

European Alpine wool is also sustainable: short transport routes protect the environment, and traditional sheep farming and processing expertise are promoted in the European wool industry. The wool material is  robust, natural, antibacterial, biodegradable, and renewable.  Our sheep's wool is a naturally renewable raw material that can be sheared annually and is biodegradable at the end of its life without leaving any residue. A biological cycle. 

Regional mountain sheep breeds have developed ideal wool fiber structures for the hot-cold climatic conditions. We use these in our sleeping bags because they promise greater moisture absorption and better climate regulation.

 

 

Wool improves sleep quality

Studies (e.g. by Woolmark Australia) show that   bedding and sleepwear made of wool

• sleeps much longer,
• falls asleep faster,
• wakes up less frequently.

The tests were conducted under warm conditions (22 °C) and cold conditions (17 °C) in the sleep laboratory using the standard polysomnography procedure.

The quality of sleep increases and you sleep more restfully with wool because it perfectly creates the ideal sleeping temperature of 33 °C body temperature for us humans. 

Other materials such as cotton or synthetics are clearly inferior to wool because they only inadequately balance heat without overheating. 

Download Wool Study German as PDF file
Download Wool Study English as PDF file

Wool sleeping bags

The Alpine wool used in our sleeping bags acts like a light, natural air conditioner : it warms and cools equally, for an all-round feeling of well-being and relaxed sleep.

• It supports our body temperature regulation. Wool can absorb up to 30% of its own weight in moisture through its capillaries and release it back to the outside in a controlled manner to prevent evaporative cooling. This not only effectively regulates moisture, but also regulates body temperature. Even when damp, it retains its warming properties, something no other material can match.
• Wool naturally creates a pleasant microclimate thanks to its unique climate-regulating properties. Wool also neutralizes unpleasant sweat odors.
• With Alpine wool insulation, your body can save itself some of the energy-sapping work of regulating body temperature. The saved energy is available for regeneration during sleep!
• By the way, couples also sleep comfortably under a blanket made of Alpine wool, because the wool fiber regulates each body temperature separately.

 

Our wool expert, the Grüezi bag sheep, chats in front of the camera about the benefits of his wool:

 

 

Wool in the outdoor area

Woolen clothing has been worn for many centuries, being functional and affordable. In our leisure society, synthetic fibers were the most popular after cotton; in the 1990s, modern functional clothing made of wool accounted for only a fraction of the synthetic-fiber-dominated sportswear retail market. Its triumphant beginnings were small but unstoppable.

Grüezi bag loves this natural raw material: wool is the only material that regulates temperature and can therefore be used across a wide temperature range! With today's processing options, we've incorporated this versatile material into sleeping bags, sleeping mats, shirts, and jackets. This saves the environment and your wardrobe from many individual, specialized products, because wool products are flexible, sustainable, high-quality, and durable. 

 Our WoodWool shirts are made from 50% merino wool and 50% wood fiber. The wood fiber content provides a velvety soft feel and a more durable fabric than pure merino shirts.

Our DownWool jackets have an excellent wearing climate thanks to the balancing function of wool.

 

 Our sleeping bags ensure a perfect sleeping environment.