With the Tokyo 2020 Games just around the corner next year, DESCENTE has unveiled its latest cooling material, Coolist D-Tec (hereafter referred to as "Coolist"). This high-performance fabric offers unprecedented sweat absorption, quick-drying, and heat-dissipating functions, essential for various sports in sweltering heat. We spoke with Mr. Tsubouchi, head of the R&D Center, about this innovative material that is sure to capture the attention of top athletes and general sports fans alike.

Coolist, the newly developed material, was first adopted in golf apparel. You can experience this new fabric in polo shirts from "Le Coq Sportif" and golf competition wear from "DESCENTE." In the Spring/Summer 2019 season, it was featured in seven brands, and next year, Coolist D-Tec is slated for use in even more brands and items.

— What are the primary methods for mitigating heat through clothing?

Tsubouchi“There are broadly two approaches to heat countermeasures. One is to block heat rays, similar to a parasol. Our company developed and began selling a summer-specific material called 'Sunscreen' in 2011, which incorporates this 'heat-shielding' function. The other effective method is to lower the temperature of the space between the body and the clothing. This involves releasing heat trapped within the garment to alleviate heat.”

— So, heat-shielding and heat-releasing are the two effective strategies for dealing with heat?

Tsubouchi“That’s correct. For instance, heat-shielding is more effective when spending extended periods under the blazing sun, while heat-releasing is more beneficial during strenuous exercise that causes significant sweating. The Coolist material I’m explaining today is specialized for heat release. It’s a material that brings coolness by utilizing evaporative heat. You can understand it by imagining sprinkling water on a hot day; it’s the same principle by which water evaporation cools the road surface by drawing heat away.”

— So, the temperature inside the clothing drops as sweat evaporates?

Tsubouchi“Fundamentally, humans sweat to lower their skin surface temperature through the evaporative heat generated when sweat evaporates. This is called effective perspiration. On the other hand, sweat that drips down without evaporating has no such effect; this is known as ineffective perspiration. Coolist’s characteristic is its ability to absorb, rapidly spread, and evaporate large amounts of sweat that would otherwise run off.”

— How much of a cooling effect can be felt?

Tsubouchi“The amount of heat dissipated by water evaporation is fixed, so it is possible to calculate, but it is heavily influenced by the usage environment. Therefore, while we cannot state a specific degree of temperature reduction in terms of specifications, we have experimentally verified that the temperature inside the clothing actually decreases.”

— For which types of sports is Coolist most effective?

Tsubouchi“Generally, sportswear can be divided into two categories: performance wear for competitive sports and uniforms for everyday use, including daily life. Depending on the sport, some events, like the 100-meter dash, are very short, so a cooling function may not be necessary. Coolist is effective for low-to-medium intensity events that last for extended periods. Golf wear was the first application for this reason.”

— What kind of fiber structure and yarn are used?

Tsubouchi“Coolist is made from a specially structured polyester yarn developed by a Japanese material manufacturer. This yarn has properties that allow it to be used in various fabric structures. Combined with our company's technology, it enables rapid sweat absorption, diffusion, and evaporation. While many quick-drying materials test results show drying within 50 minutes to an hour, Coolist dries at double the speed. This significantly enhances comfort, preventing stickiness against the skin even when sweating and maintaining a smooth feel.”

— For athletes, sweat can be a distraction, so Coolist must be very effective.

Tsubouchi“Coolist offers excellent benefits in situations requiring stress-free performance, such as pre-competition concentration and post-competition relaxation. Our mission is to make as many athletes as possible feel, 'I'm glad I wore this,' and we want all sports fans to experience it. Internally, the feedback on Coolist wear among our employees has been very positive, so we have high expectations.”

— How does DESCENTE conduct its research and development?

Tsubouchi“We have a 20,000-square-meter R&D facility in Ibaraki, Osaka, called DISC (DESCENTE INNOVATION STUDIO COMPLEX). There, we collaborate with various athletes who assist with tests and measurements, and the data obtained is utilized in our research. The extensive grounds were necessary to accommodate measurements for a wide range of sports, including track and field, soccer, and golf. In addition to our own engineers, we invite external experts, including researchers from universities, to objectively assess our technologies during the R&D process.”

— The first DISC is in Ibaraki, Osaka, and the second DISC is in Busan, South Korea. What are the reasons behind these locations?

Tsubouchi“A major reason for DISC Osaka, our R&D hub for sports apparel, being located nearby is the presence of many development research labs from major Japanese material manufacturers, enabling collaborative R&D. Similarly, DISC Busan, responsible for sports shoe development, is surrounded by many companies and factories related to footwear, allowing for a more efficient completion of the entire process from research and development to product manufacturing.”

— Architecturally, DISC is also innovative, featuring cutting-edge laboratories that seem straight out of a science fiction movie.

Tsubouchi“Our offices in Osaka and Tokyo are primarily white, but DISC is black. We chose this to help shift our mindset upon arrival, allowing us to focus solely on creation. Inside DISC, we operate on a free address system where desks change daily, breaking down departmental barriers. This fosters information sharing among all DISC members and encourages flexible thinking. For development, we assemble project teams comprising not only researchers and technicians with specialized knowledge but also individuals from diverse backgrounds, including designers, marketing, and even accounting. By having members with completely different approaches and perspectives brainstorm together, we achieve unique discoveries like, 'Ah, that's the way to do it!'”

— For functional wear recognized by top athletes to be understood by general sports fans and fashion enthusiasts, design will become an increasingly important element, won't it?

Tsubouchi“Appearance is certainly important, but for us, design also refers to the combination of function and technology. Simply combining different technologies to achieve functionality often doesn't work well and can lead to customers not perceiving value. We believe the true essence of design lies in considering the optimal functionality for the customer, and when that is realized into a final product through our technological capabilities, the functionality naturally manifests visually, resulting in product design. For example, in DESCENTE's Allterrain category, the technique of using bonded seams instead of stitching to enhance waterproofing directly led to the design of the 'Mizusawa Down' product.”

— Regarding sustainability and ethical practices, which are increasingly demanded of apparel companies, what initiatives is DESCENTE undertaking?

Tsubouchi“We are implementing initiatives to reduce environmental impact across various brands, such as adopting dyeing techniques that use minimal water and increasing processes that do not require boilers. On a company-wide level, we are transitioning to environmentally friendly water-repellent agents. Previously, we used a C8 repellent, which offered high durability but did not decompose naturally, posing a significant environmental burden. Therefore, we have switched to the more environmentally friendly C6 repellent across the entire company. However, globally, the trend is shifting towards carbon-free water-repellent agents, and we recognize that DESCENTE's sustainability efforts are still evolving.”

— With products like DESCENTE Allterrain and Mizusawa Down, which you mentioned earlier, the brand has gained wider recognition among fashion enthusiasts in recent years. What does the future of DESCENTE's research and development look like?

Tsubouchi“'Mizusawa Down' is a seamless down jacket born from the accumulated technology cultivated at our production sites. It cannot be achieved solely through heat-bonding technology. Rather than simply adopting and commercializing any technology we happen to discover, we focus on original research and development and creating products with a compelling story. We believe this approach ultimately leads to unique products that cannot be easily replicated by competitors.”

Mr. Tsubouchi, a professional in sports textiles, holds a qualification as a Certified Specialist in Textile Quality Management. He juggles busy schedules between the Osaka headquarters, DISC Osaka, and Tokyo, engaging in cutting-edge research and development.