Wool is a natural material that is made from the hair of sheep or llamas. These hairs have hollow cells that trap air, allowing the wool to retain body heat. This property of wool is known as thermal insulation. As with double glazing windows, it is this captured air that isolates you from the outside. This is why wool or cashmere socks are warm.
Wool also has hygroscopic properties, meaning it can absorb up to 30% of its weight in moisture without feeling damp. This means that wool can absorb moisture from your body's sweat and release it to the air, keeping you dry and warm.
In addition, wool has a temperature regulating property, that is, it can adapt to your body temperature. It can keep you warm when you're cold and cool you when you're hot. This property is due to the ability of wool to regulate the exchange of air between the inside and outside of the fiber.
Wool is also a durable material. It is quite resistant to wear, tear and fading. Note that the finer the fibers, the softer they are but also the more fragile they are. Thus, cashmere is more delicate than rustic wool. Wool is also flame and stain resistant, making it ideal for workwear and outdoor clothing. For socks, this quality is secondary.
Additionally, wool is eco-friendly and durable. It is made from renewable raw materials and can be recycled or composted. It is also environmentally friendly as it does not require pesticides or chemicals for its production. Concerning animal welfare, it should be added that mowing in spring is beneficial for animals. Shearing the wool reduces the risk of infection for sheep and prevents them from getting too hot in summer. They can thus develop better.
In France, for example, some breeders have their sheep sheared just for the comfort of the animals. Indeed, even if the wool is sold, its price is lower than what the person who shears the animals charges.
Finally, wool is naturally anti-bacterial. For example, when you put on a wool sock, you will see that at the end of the day it smells much less than a cotton sock (or worse a synthetic sock).
In summary, wool is a natural material that is made from the hair of sheep or llamas. It is insulating, hygroscopic, temperature regulating, resistant, anti-bacterial, ecological and durable. All these properties make wool an excellent material for good , very warm socks .