Synthetic or wool—the question of which material to choose for active wear has long been debated by the likes of runners, trail runners, and hikers. Hikers tend to prefer merino wool for its advantages like good hand feel, odor resistance, and the ability to reduce post-exercise chill; but synthetics are more quick drying, lightweight, and durable. Many manufacturers use materials made of mixed yarns with the hope of reaping the benefits of both wool and synthetics. The problem with conventional wool–polyester blends, however, is that the material pills easily and it feels like polyester to the touch.

“We wanted to offer clothes for outdoor activities that are made of natural materials and feel as comfortable as lounge wear. So we searched for a material that lived up to our ideals,” says Yuya Kobayashi, the performance wear merchandiser in the planning group of the Goldwin business unit at Goldwin Inc. Mr. Kobayashi and his team discovered their ideal material at a yarn mill in Gifu Prefecture. It’s called NIKKE AXIO®︎.

NIKKE AXIO®︎ is a blended yarn—composed of two or more different fibers—but whereas conventional wool–polyester blends wrapped the polyester fiber around the outside of the wool fiber bundle, NIKKE AXIO®︎ is created with a completely new spiral-structured polyester fiber wrapped inside the wool fiber bundle. Because the polyester is not exposed on the yarn surface, NIKKE AXIO®︎ retains the exceptional texture and hand feel of pure wool. It also has all the other functions of wool, such as the ability to reduce post-exercise chill, absorb and release moisture, and resist odors; and thanks to the polyester core, it’s lighter weight, quicker to dry, and has more stretch and wear resistance than pure wool yarns. Not only that, it even solves the problems of conventional wool blends, like hand feel and pilling. In short, NIKKE AXIO®︎ is a hybrid yarn with the best of both worlds.

Tomonori Yasuda, the head of the Gifu Factory of Japan Wool Textile Co., Ltd., the developer of NIKKE AXIO®︎, says, “With conventional wool–polyester intertwisted yarns, the rough feel of polyester came on the surface, and the garment lost the comfort of the original wool yarn. It was possible to spin a core of polyester into the wool fiber bundle, but the wool and polyester easily became separated. With this spiral structure, we took on a challenge no other maker had ever attempted before. The completed yarn has the advantages of both wool and synthetics, and thanks to the fiber structure, it has added stretch and anti-pilling benefits too.”

Mr. Kobayashi says, “In recent years, hikers prefer base layers made of merino wool for its advantages like resistance to post-exercise chill and odors. NIKKE AXIO®︎ has all these features of wool, plus it’s moisture wicking and durable—what a perfect yarn for making garments for long hours of activity, like hiking and trail running. We decided to use that yarn in a knitted fabric and develop Goldwin active wear.”

After spinning in the yarn mill in Gifu Prefecture, NIKKE AXIO®︎ is sent to a knitting mill in Bishu (Ichinomiya City, Aichi Prefecture), one of the world’s three major heritage wool textile production areas. The Bishu production area is home to seasoned knitters trained in the handling of all kinds of yarns, from natural to synthetic. Here, the yarn is processed into knitted fabric.

Takashi Miyata of Miyata WF Co., Ltd. says, “In the eyes of a professional knitter, NIKKE AXIO®︎ wool is less prone to pilling than other wool yarns, and it comes complete with the strength of polyester. Because the yarn itself has great strength, it’s less vulnerable to breakage in the circular knitting machine and can be knitted efficiently.”

The undyed knitted fabric using NIKKE AXIO®︎ then goes to another mill in the Bishu production area for dyeing and finishing to create the desired texture and add various functional properties. In the process of dyeing the fabric, special chemicals are used to apply moisture wicking, shrink resistant, and anti-pilling treatments.

Naoki Okumura, head of the Nikka Factory at K.K. Sotoh, specializing in dyeing and finishing, says, “Natural wool is moisture resistant, so it takes some time to absorb sweat. That’s why we apply a moisture wicking treatment. Because NIKKE AXIO®︎ is a blend, we do that in two steps—we treat the wool in the pre-treatment stage, and the polyester in the post-treatment stage—and give the fabric the moisture wicking function.”

After dyeing and finishing, the bolt of knitted fabric is unrolled and fed through a dryer, where the width of the fabric is adjusted and evened out. Finally, the nap is set with tension and hot steam in a decatizing process unique to the mill in the Bishu production area. This finishing touch adds a smooth luster to the fabric surface and helps the garment hold its shape.

The completed fabric is finally used to make the Goldwin products Wool Long Sleeve T-shirt and Wool T-shirt. Both items are amazingly comfortable and highly functional; they meet the exacting Woolmark standards for qualities such as color fastness, shrink resistance and shape retention after washing, anti-pilling, and durability set by the Woolmark Company, and have obtained global Woolmark certification, an assurance of high-quality wool products; plus they’re easy to care for—a combination of features that is welcomed by athletes.

NIKKE AXIO®︎ merino wool shirts are a favorite of top athletes as well as Mr. Kobayashi and the other members of the development team, who wear the shirts both on and off duty. And it’s the summer months ahead, when thermoregulation properties are a must, that will give full play to the shirts’ features and benefits.

“The quick drying and breathable properties make the wool material even more comfortable to wear in the summer. It’s perfect for activities like running, trail running, and trekking,” says Mr. Kobayashi. “This is comfort created with Japan’s advanced technology, and I invite everyone to try it out in the field.”