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Yak and merino Wool Clothing

You might know Merino, but have you ever heard worn yak down, AKA "khullu"?
Jan 4, 2021
By Oliver Charles
Wool comes in many different forms with different feel and function. Animals in the families of sheep, goats, yak, camel, and even ox produce a fiber broadly called "wool".

It doesn't even come close - wool is the world's best performing material, and khullu and merino are the best overall type of wool.

Khullu, the foundation of our yak wool clothing, comes from the soft underbelly fibers that insulate yak in the cold winter.

Our materials helped us make both a warm wool sweater and a highly breathable sweater.

How warm is yak and merino wool?

Unlike human hair, wool has crimps, which are natural "waves" in the fiber that trap air, insulating in extreme colds and wick vapor, cooling in extreme heat.

Wool can be regarded as an ‘active’ fiber, which keeps body temperature at an equilibrium - it efficiently transfers water vapor from sweat in and away from the body as temperatures change. In fact, as wool transfers water vapor, a chemical reaction occurs that produces heat.

Yak, who grow a thermoregulating fiber called khullu live in a high elevation climate that varies between -40° F in the winters to 90° F in the summers. Even the desert-living Bedouins wear lightweight wool like ours clothing to keep themselves cool (Fleece and Fiber).

Soft Sweater Material

The most important factors impacting sensitivity is the fiber fineness. While a human hair has a average diameter of 75 microns (µm), the wool we use in our sweaters is ultra-fine at 17.5µm. So is yak and merino wool itchy? It depends on the fiber's fineness. Wools that are generally considered "soft" have a fineness <20µm.

Odor Resistant material

Wool is antimicrobial, which starts with the materials wicking properties - in order to regulate body temperature, humans can sweat several liters a day. All this sweat can get pretty smelly right? In fact, sweat only becomes odor if it isn't wicked away. Wool has a number of unique moisture management properties that allow it to resist body odor making it ideal for #repeat wear and simplifying your life

Saturation regain: wool can absorb and retain up to 35% of its own weight in moisture and still feel dry to the touch, which reduces sweat buildup and discourages bacterial growth.

Isolation of bacteria: after sweat is absorbed from the skin's surface it travels outwards where it evaporates. In the process, wool actively binds and isolates bacteria within it's fiber. The isolation of bacteria reduces odor to the point where unwashed wool has 66% less odor intensity than plastic-based fibers and 28% less than cotton fabrics (Woolmark).

Fun fact: bacteria thrive in humid environments, where sweat is trapped instead of being wicked away. For example, while a 1x1cm area on a human forearm contains around 100 bacteria, an identical square in the armpit contains on average 10 million bacteria (Popular Science).

The odor resistant properties of wool allow clothing be washed less, worn more, and always left smelling/feeling fresh, even after the 10th wear. You may travel with wool layers for just this reason.

is yak and merino wool durable?

The crimps in wool are akin to a molecular coil spring. The fibers naturally expand and contract according to their environment. The crimps allow wool fibers to be stretched up to 50% of their length when wet / 30% when dry and still bounce back to their original shape when stress is released.

The flexibility gained from wool crimps makes the fiber more durable
. Merino wool, for instance, can be bent back on itself more than 30,000 times without breaking, compared to about 3,000 times for cotton and 2,000 times for silk (American Wool)

Sustainable Work Clothes

Compared to both synthetics and many cellulose-based fibers, wool is far more sustainable. Wool is a 100% regenerative material, which is in many cases naturally shed. Being a natural material, wool biodegrades in just a few months vs. up to 200 years in the case of plastic-based fibers.

Wool is also self-cleaning, meaning it will release bacteria and odor even in a cold wash, which is great news because 25% of the carbon footprint of clothing comes from its lifespan of care (Fashion Revolution).
If you believe that every good wardrobe starts with owning less and owning better, consider buying yourself an OLIVER CHARLES sweater.
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