[Mother’s Day] Alongside a bouquet of gratitude, add one more gift: the comfort that lasts beyond the day. A magical T-shirt that cares for the skin and brings a smile to Mom’s face.

【母の日】感謝の花に、もう一つ「心地よい時間」を添えて。お母さんが喜ぶ、肌を労わる魔法のTシャツ - C-one ONLINE STORE

Mother’s Day falls on May 11 this year. Classic carnations and sweets are always lovely, but why not add one more gift this year—“comfort that lasts every day”?

A bouquet brightens a special day. But perhaps the truest gift for someone dear is something that, the next day and the day after that, still makes them feel, in the middle of everyday life, “This was chosen just for me.” Here is why C-one’s Merino wool T-shirt has become a thoughtful choice for Mother’s Day gifting.

THE SCIENCE OF TOUCH “Wool feels itchy” was really a matter of fiber diameter

The idea that “wool is itchy” is, more precisely, that “coarse wool feels itchy.” The threshold at which human skin begins to perceive prickliness is said to be around 22μm (micrometers) in fiber diameter. Once fibers exceed this level, their tips can stimulate pain receptors in the skin, creating discomfort.

The Super 100’s grade Merino wool used by C-one has a fiber diameter of 18.5μm. This fineness—3.5μm below the threshold—is what creates that silk-like smoothness you can feel the moment you slip it on.

Itchiness Threshold
Approx. 22 μm
Below this, irritation is not felt
C-one Super 100's
18.5 μm
3.5μm below the threshold
Standard Wool
28–35 μm
Above the threshold and prone to itchiness
C-one Super 100's (18.5μm) Itchiness Threshold (22μm) Standard Wool (28–35μm)

Figure 1: Comparison of fiber diameters among major materials. Once below 22μm, human skin no longer perceives prickliness. C-one falls well below that threshold.

SKIN & FIBER SCIENCE

As we age, the stratum corneum of the skin becomes thinner, making it more sensitive to external irritation. This is why many women in their 40s and beyond begin to feel that materials which never bothered them in their younger years no longer suit their skin. Fine-fiber Merino wool is one of the few natural materials that can adapt to this change. It is also free from the frictional irritation often caused by synthetic fibers, making it a reassuring choice for sensitive or dry skin.

THERMOREGULATION The scientific reason women’s bodies are more vulnerable to feeling cold

Compared to men, women tend to have less muscle mass and a lower basal metabolic rate. Because muscle is the primary tissue responsible for generating heat in the body, this difference is directly tied to the physiological reality that women are generally more sensitive to cold. In addition, fluctuations in the autonomic nervous system caused by the menstrual cycle can affect thermoregulation. Especially during May and June, when the temperature gap between hot outdoor air and cold indoor air conditioning is at its peak, the body expends substantial energy trying to regulate its temperature.

If clothing could take on some of that “thermoregulatory burden,” that would be exactly what Merino wool’s “natural air conditioner” function does.

Outdoors / Hot
Sweating and rising body heat
Merino releases moisture vapor
Moisture escapes while the fibers stay dry inside
Stable perceived temperature
Less stuffy, less sticky, and more comfortable
Whether it is hot outdoors or cold indoors, Merino wool helps adjust comfort naturally.
Indoors / Air Conditioning
Surface body temperature drops
Warmth through heat of sorption
Gentle heat is generated as moisture is absorbed
Helps ease the chill
Reduces the stress caused by sudden temperature changes

Figure 2: Bidirectional thermoregulation of Merino wool. When it is hot, it helps release moisture as vapor; when it is cold, it helps retain gentle warmth through heat of sorption.

WOOL HYGROSCOPIC MECHANISM

Wool fibers generate “heat of sorption” because the cortex inside the fiber releases chemical bonding energy as heat when it absorbs water molecules. This phenomenon is known as “Heat of Sorption,” and wool is said to generate approximately 27 kcal of heat per kilogram. This gentle warming effect helps soften the cool sensation the body feels in air-conditioned environments, making it a scientifically sensible feature for women who are sensitive to the cold.

THE GIFT OF TIME A gift that helps reduce the stress of housework

When choosing clothing as a Mother’s Day gift, there is one perspective that is often overlooked: “Who will be washing and caring for this garment?” Delicate fabrics can be difficult to manage and may end up becoming a burden instead.

C-one’s Merino wool is the opposite. Thanks to its natural resistance to dirt and odor (supported by the weakly acidic nature of the lanolin layer), it is less likely to pick up stains or smells, requires less frequent washing, and does not need ironing. Instead of gifting something that adds more work, it becomes a gift that helps reduce the time spent on housework.

Comparison Point C-one Merino Wool Standard T-shirt
Feel on Skin 18.5μm / Non-itchy Friction irritation from synthetic fibers
Thermoregulation Automatically adjusts through moisture absorption and release Dependent on temperature / managed by layering or removing clothes
Odor & Stain Resistance Naturally suppressed by the lanolin layer Depends on washing frequency
Ironing Not needed (natural recovery through fiber crimp) Often necessary

UNISEX DESIGN Because you wear it yourself, you can gift it with confidence

C-one is a unisex brand. Because you have actually worn it and know how comfortable it feels, you can share that experience with someone important to you. A gift backed by the feeling of “This really feels amazing” carries more persuasive power than words ever could.

Choosing different colors as a pair and wearing them on your next trip or everyday outing together—this too is part of the unique enjoyment that only C-one can offer.

A gift that lasts beyond the day the bouquet is given.

With silk-like softness, a natural air-conditioning function, and an easy-care design that needs neither frequent washing nor ironing, C-one’s Merino wool T-shirt is a gift that lets the wearer feel, every time they put it on, “This was chosen for me.”

Gift wrapping is also available. Put your gratitude into one truly exceptional piece.

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