A Fresh Take on Shirt Fabrics for Sweltering Summers: Unpacking the High-Airflow Design of Nisshinbo Textile's 'Cool Method AT'

With scorching hot days becoming the new normal, enhancing clothing comfort is a critical challenge for the apparel industry. Enter "Cool Method AT," a new fabric developed by Nisshinbo Textile Inc. It grabbed headlines after being used in men's shirts in 2025 and becoming a massive hit. Its standout feature—a high performance with an airflow rate over 100cc—is the culmination of more than ten years of research and development.

We sat down with Masashi Fujitani from the company's Shirt Division and Daisuke Tanaka from the Marketing Promotion Office to discuss the story behind the fabric's development and its technological breakthroughs.

The Birth of a New, Highly Breathable Fabric

Enhancing summer comfort—this has long been a core mission for Nisshinbo Textile. The extreme heat of recent years has presented a fresh challenge for fabric developers, especially from a heatstroke-prevention standpoint. Against this backdrop, "Cool Method AT" was born, achieving phenomenal breathability through an innovative weave structure.

The fabric’s key feature is its honeycomb weave—a structure made up of interconnected hexagons. This unique design achieves an airflow rate of over 100 cc per cm² per second, significantly exceeding the typical 60 to 80 cc per cm² per second found in conventional high-airflow shirt fabrics. As a result, it promotes efficient air circulation and greatly reduces that stuffy feeling.

"We've been dedicated to improving breathability for over a decade," Fujitani shared. Indeed, the company has developed numerous high-airflow woven fabrics in the past.

Traditionally, increasing airflow meant reducing the yarn count to lower the fabric's density. The downside, however, was that this made the fabric more transparent, compromising its premium look and feel.

In contrast, "Cool Method AT" achieves its impressive breathability purely through weaving technology while maintaining its density. The technique has been lauded internally. "To reach an airflow rate of 100cc using only weaving technology gives us a unique sense of accomplishment, different from what we've felt with past materials," Fujitani stressed.

Recreating a Unique Weave on a Dobby Loom, Inspired by Leno Weave

The honeycomb structure of "Cool Method AT" draws inspiration from a traditional technique known as "karami-ori," or leno weave, long used in summer fabrics. Leno weave is a special method where two warp threads twist around the weft thread, creating gaps that make the resulting fabric highly breathable.

However, this technique came with a significant hurdle. Production requires a specialized loom that very few manufacturers in the industry own. What's more, the complex structure slows the weaving process, driving up production costs. For manufacturers, making a hefty investment in equipment for a material used only in summer was a risky proposition.

That's when Nisshinbo Textile tried something new: recreating the feel and function of a leno weave using a standard dobby loom. Since dobby looms are widely available for creating patterned fabrics, this approach promised major cost savings and a huge boost in productivity.

"We experimented to see if we could create something similar to a leno weave using our existing equipment," Fujitani recalls. The result was the birth of "Cool Method AT," a fabric that not only mimics the crisp feel and high breathability of leno weaves but also dramatically boosts production efficiency.

Overcoming Sheerness and Pattern Distortion with a Meticulous Design

However, applying this technology wasn't without its challenges. Highly breathable fabrics, by their very nature, have gaps in their structure, which leads to the drawback of increased sheerness when worn.

What's more, the textured surface of the honeycomb structure introduced another hurdle: attempts to create patterns like stripes or checks resulted in the weave pulling and distorting the design.

But the team had already anticipated these issues. They tackled the challenges by applying insights from their concurrent research into the "pattern camouflage effect." This technique leverages the visual properties of certain patterns to make sheerness and wrinkles less apparent. With "Cool Method AT," they ingeniously minimized transparency by designing the weave itself to resemble vertical stripes.

On top of that, the unique weave structure brought its own set of physical challenges, including seam slippage—where threads shift and seams open under pressure—and pilling from friction.

To overcome these tough obstacles, the development team produced a huge number of prototypes and meticulously analyzed more than a decade of data on high-breathability materials. They persisted with the painstaking work of finding the perfect overall design, fine-tuning everything from thread thickness and tension to the balance of the weave.

Next-to-Skin Comfort and Feel from the Textured Structure

The comfort delivered by "Cool Method AT" goes beyond just breathability. The fine, textured surface created by the honeycomb-style structure provides another key function: a fantastic next-to-skin feel.

The textured fabric makes point-contact with the skin. This means that even when you sweat, the fabric is less likely to cling, maintaining a dry, comfortable feel. This quality is extremely effective in reducing the unpleasant stickiness of summer.

According to Fujitani, this textured surface was actually a byproduct of the quest for high breathability. However, since a fabric's ability to stay off the skin is a crucial element in summer material development, the structure turned out to be perfect, delivering multiple comfort-enhancing benefits.

In line with the company's core philosophy, they also recommend a 100% cotton version. Cotton outperforms polyester in moisture absorption, making it less stuffy, and its natural, pleasant feel significantly boosts wearer satisfaction.

Of course, because "Cool Method AT" is a weaving technique and not material-specific, it can be customized to meet client needs. It can be blended with moisture-wicking, quick-drying polyester or treated with various finishes to add functionality.

What's more, this comfort isn't just a feeling—it's backed by objective data. In-house testing has shown that the temperature inside a "Cool Method AT" garment is approximately 2°C lower than in a conventional business shirt.

New Frontiers: Expanding into Workwear and Loungewear

Last year, "Cool Method AT" was featured in a line of men's business shirts and garnered rave reviews. Consumers love its versatility; the fabric has a sophisticated texture perfect for the office but is equally suited for casual styles.

According to Tanaka from Nisshinbo Textile's marketing team, the success of their business shirts is just the beginning. They see potential for the material to be used in a much wider range of situations.

One promising area is workwear. For those working outdoors on sites like construction projects, preventing heatstroke is a critical challenge. With its excellent breathability and non-stick feel, this fabric is poised to make a major contribution to the safety and comfort of people working in tough conditions.

Loungewear and sleepwear are also promising markets. The material’s unique texture and functionality make it perfect for reducing the discomfort of night sweats and supporting a good night's sleep.

Tanaka seems confident about the market's reception, noting, "We've been getting feedback that people see great potential for it in loungewear and sleepwear."

Naturally, the expansion into casual shirts and everyday wear is also picking up speed. "Our goal isn't just about this one business shirt," Tanaka explained. "We aim to create value by combining it with various other textiles to produce truly innovative cotton materials."

Built on traditional weaving techniques, "Cool Method AT" continues to innovate to meet today's needs. It looks set to become a go-to material for enhancing comfort in a wide variety of everyday situations.