Why Good Wool Makes a Difference the More You Wear It
Why a Short-Sleeve Merino Tee Feels Comfortable—even in the Cold
A merino wool T-shirt feels comfortable even when brand new. At the same time, it’s also a material that gradually develops as you wear and wash it.
Not just how it feels the moment you put it on, but how it feels after being worn regularly in everyday life— that’s where the real difference in materials becomes apparent.
Start by seeing the difference in fiber thickness
When people hear “wool,” many imagine something thick and scratchy. In reality, wool fibers vary widely in thickness, and thicker fibers tend to cause more irritation.
Below is a visual comparison of fibers seen under magnification. From left to right: typical cotton, human hair, and Super 100 merino wool.
Twists on the surface and variations in thickness are common.
A reference point to help visualize fineness.
Exceptionally fine, uniform, and smooth on the surface.
Fiber thickness influences the first sensation against the skin. However, it doesn’t determine comfort on its own.
“Super 100” as a reference for fine wool
One commonly used benchmark for fine, well-balanced wool is Super 100. This is not the name of a yarn or fabric, but a reference indicating that the raw wool fibers measure approximately 18.5 microns or less.
At C-one, we select yarns and fabrics suitable for daily wear by understanding these material characteristics and how they behave over time.
Yarn count, ply, and construction make the difference in daily wear
For C-one T-shirts, we use 72/2 yarn made from Super 100–grade merino wool.
The fineness of the yarn creates a natural luster. The two-ply construction adds stability. Together, these elements help the garment resist distortion even after repeated washing.
Each piece is carefully sewn, one by one, at a sewing factory in Fukushima. It is construction designed for garments meant to be worn regularly—not occasionally.
Why a material chosen for harsh conditions feels comfortable in daily life
Merino wool has long been used in demanding environments such as mountaineering and long-distance travel.
It resists chilling even when you sweat. It adapts well to temperature fluctuations. It remains comfortable even when worn on consecutive days.
The requirements of harsh environments translate into a sense of ease in everyday wear.
How the fabric changed with continued wear
- Length: approximately 2–3 cm shorter than when new
- Width: no significant change
- Fabric: softer, with a greater sense of conformity to the body
- Color: even black T-shirts showed minimal fading and retained depth
Wool fibers naturally hold dye within their structure, making them more resistant to fading compared to cotton. (Of course, washing and drying methods still matter.)
Reference: typical fiber thickness
| Material | Fiber thickness | Notes |
|---|---|---|
| Typical cotton | Approx. 20–30 μm | Practical and easy to handle |
| Human hair | Approx. 80 μm | A reference point |
| Super 100 merino (raw wool) | Approx. ≤18.5 μm | Supple and gentle on the skin |
*Values shown are general references. Comfort is determined by multiple factors including yarn, knitting, and construction.
A T-shirt that quietly fits people like this
- Those who want to use what they love for as long as possible
- Those who prefer to understand why before choosing
- Those who value comfort in everyday life
A piece we recommend experiencing first
Comfortable on its own in summer.
Quietly supportive as an inner layer in winter.
This is our most straightforward expression of C-one’s philosophy.