Wool for insulation filling and clothing

Wool as a sustainable functional material

Wool from sheep, goats and alpacas has been used for textile production for centuries. Who doesn't know the wool sweaters from grandma's time, often scratchy and misshapen, felted and not machine washable? So how do you 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 irreplaceably valuable for everyday life, traveling or sport:

  • You don't need to iron wool clothes because they are wrinkle-resistant.
  • Wool clothing doesn't scratch (anymore).
  • Wool clothing absorbs dirt and odors very little, 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, 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 such as hemp, cotton or silk cannot. The physical structure, chemical and physical properties explain the advantages of the miracle weapon wool.

Structure of the wool fiber

Structure of the wool fiber

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

  • Wool fibers consist of a coat (cuticle) and a core (cortex). The cuticle is a tile-shaped scale layer whose outermost layer consists of lipids and is therefore hydrophobic (water-repellent).
  • Wool consists of 97% proteins, whose amino acids can bind water. Wool fibers can absorb up to 33% of their own weight in water. This is called hygroscopic behavior.
  • A single wool fiber consists of many components that are built up in layers. Air-filled cavities form between these layers. A wool fiber therefore consists of up to 85% air (calculated based on its total volume).
  • The protein components of the wool fiber are the reason for the mechanical functionality of wool: stretchy, flexible, elastic, tear-resistant. Wool fibers look like spiral springs, they are heavily curled. The finer the wool, the more strongly the wool fibers are twisted into each other in a spiral shape.

Wool clothing hardly wrinkles

Wool clothing is ideal for traveling: the wool fiber is elastic and strives to always return to its original state. Therefore, wool clothing is ideal for backpacking or taking with you when traveling; it wrinkles little.

Wool clothing hardly scratches these days

In the past, thick sheep's wool sweaters usually itched terribly. And thank God that is now a thing of the past. The coarser the sheep's wool, the less curled it is and the more cuticle of the wool fiber lies on the skin. This is the reason for a scratchy feeling on the skin. We humans find wool fibers with a diameter of around 25 microns to be unpleasantly scratchy.

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

Fine wool is highly arched and strongly curved (up to 40 changes of direction/cm), and has a finer cuticle layer, so the wool fiber lies only minimally on the skin. Therefore, a wool shirt from Grüezi bag feels soft and comfortable on the skin.

Wool clothing is water-repellent

  • The tile-shaped cuticle of a wool fiber and its outermost layer are naturally water-repellent.
  • The wool fat lanolin also contributes to the water-repellent effect because, as a protective layer on the fiber, odors and grease do not penetrate into the interior of the wool fiber.
  • In addition, the strongly crimped fibers create a beading effect for water droplets.

We also know this effect from nature, where plants like the lotus plant gave the name to the way it works: lotus effect.

In earlier times without plastic or even GORE-TEX, people protected themselves from the rain with wool clothing, such as the well-known felt hat, a tightly woven wool material, or wool jackets, which protect against rain to a certain extent.

Wool clothing is dirt-repellent and odor-resistant

The outer cuticle is a natural protective shield against dirt and stains. In addition, the wool fibers rub against each other during the moisture absorption and release process, so dirt cannot settle as easily.

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

Sweat initially consists of over 99% water and less than 1% salt ions and proteins. The smell of sweat only arises during the decomposition process on the skin by skin bacteria. These have less chance of settling on the scale-shaped and water-repellent outer skin and, due to the rapid removal of moisture, they lack the moist environment to spread. Sheep's wool even absorbs odors into the fibers and only releases them again when washed.

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

Wool is insulating in cold and heat

Wool contains a lot of air volume in the fibers and due to its crimped fibers. Since air conducts heat poorly, our body heat is perfectly insulated against the cold or hot outside temperature.

We therefore also recommend wool shirts in summer. Although it may sound contradictory at first, it is not only recommended for stays in the sun, but also when moving to cool, air-conditioned interiors. Best worn in layers, wool shirts are a real secret weapon for a comfortable temperature on warm and cold days!

Wool also insulates when wet

Sweaty synthetic functional clothing feels wet and sticky on the skin. Wool can absorb up to a third of its own weight in moisture without any chilling effect. The capillary effect of the wool fibers is responsible for this:

The fine wool fibers absorb the condensed sweat until it is saturated, then release the moisture into the outside air. The steam condenses and releases energy in the form of heat of condensation. So as long as the wool fibers can absorb moisture, they release heat to the body.

This means: Wool ensures a good microclimate on the body, because despite sweating, wool feels temperature-balancing on the skin and moisture is absorbed without strong evaporation cold. 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 little digression: Why do we sweat?

The human body temperature must remain as constant as possible and may only deviate slightly from its target temperature of 37° Celsius on average. When you overheat, the body tries to give off heat as quickly as possible: through heat release and sweating. When the release of heat into the surrounding air alone is no longer sufficient, sweat comes into play. Up to 4 million sweat glands are located almost everywhere on the surface of the body. These can release up to 3 liters of sweat per hour during vigorous 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, the cooling for the body.
  • The evaporation process removes energy from the environment and the air becomes 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 the body temperature through moist wraps. Evaporation works best when there is low humidity, strong winds, high air temperatures and high levels of sunlight.

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

Grüezi bag uses the filling wool of sheep from the Alpine region for its sleeping bags. It is processed and delivered by the well-known wool supplier lavalan®. Buyers can use track & trace labels on the sleeping bag (hangtag) to trace the origin of the wool “from sheep to shop”.

The wool processed by lavalan is light, washable and processable in the form of a fleece fabric, ideal for outdoor use: the wool is brushed on, so in addition to the wool fiber, the wool layer can also store a lot of air and is loose and light. So that it remains loose and yet washable, it is glued with corn starch (PLA).

Alpine wool by lavalan lavalan® Alpine wool fleece

European Alpine wool is also sustainable: short transport routes protect the environment, traditional sheep breeding and know-how in processing in the European wool industry are promoted. 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 can be broken down again at the end of its life without leaving any residue. A biological cycle.

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

Wool improves sleep quality

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

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

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

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 significantly inferior to wool because they do not adequately balance the heat without overheating.

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

Wool sleeping bags

The alpine wool used in our sleeping bags acts like a light, natural air conditioning system : it warms and cools in equal measure, for an all-round feeling of well-being and a relaxed sleep.

  • It supports our body temperature regulation. Wool can absorb up to 30% of its own weight in moisture via its capillaries and release it back to the outside in a measured amount - so that no evaporation cold occurs. This not only ensures effective moisture regulation, but also body temperature regulation. Even when wet, it retains its warming properties, something no other material can do.
  • Wool naturally creates a cozy and pleasant microclimate thanks to its unique climate-balancing properties. The wool also neutralizes unpleasant sweat odors.
  • With AlmWolle insulation, the body can save itself some of the energy-consuming work of regulating body temperature. The energy saved is available for regeneration while you 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

Wool clothing has been worn for many centuries, is functional and affordable. In our leisure society, after cotton, it was mainly synthetic fibers that were used; modern functional clothing made of wool only made up a fraction of the synthetic fiber-dominated sports retail trade in the 1990s. The triumphal march began small but unstoppable.

Grüezi bag loves this natural raw material: wool is the only material that regulates temperature and can therefore be used in a wide temperature range! With today's processing options, we have used the all-rounder in sleeping bags, sleeping mats, shirts and jackets. This saves the environment and the wardrobe many individual special products, because wool products are flexible, sustainable, high-quality and long-lasting.

Our WoodWool shirts are made from 50% merino wool and 50% wood fibers. The wood fiber content ensures 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.