Achieving Incredible Lightness & Mobility! The Appeal of Goldwin's Technology-Driven "Waterproof Breathable Jacket"

At first glance, this Waterproof Jacket appears simple. However, despite its understated look, it is packed with numerous innovations that are immediately felt by the wearer.

This is no surprise, as it was developed in collaboration with Goldwin's top-notch technology, fine-tuned by world-class trail runner Dylan Bowman.

We spoke with Yuya Kobayashi from Goldwin, who led the development, to uncover the secrets hidden within this waterproof jacket.

Focus on Detail to Achieve "Lightness"

"Goldwin originated in skiing but expanded into the outdoor category in 2019. However, we didn’t have products specifically for trail running, which lies between climbing and running.

"As a result, we decided to develop products for trail runners, drawing on insights gained from Dylan Bowman’s career, and started this project in 2022."

One of the representative items is the "PERTEX SHIELD AIR Fast Run Jacket," which is designed with two main focuses.

First is its "lightness." In trail running races, participants must carry all necessary gear themselves. Depending on the event, the duration can stretch into a full day and night, requiring a diverse range of items such as hydration, energy food, and a headlamp. Thus, minimizing weight is a pivotal challenge for trail runners.

This jacket has pursued lightness to the extreme, achieving a weight of just 105g in size 3 (equivalent to L size). However, what’s remarkable about this jacket is that its functionality is not compromised by its light weight.

"While typical rainwear uses waterproof and breathable materials, this jacket incorporates 'PERTEX SHIELD AIR,' which excels in waterproofing, breathability, and ventilation.

"During trail runs, it’s common to sweat or experience temperature rises after rain, leading to internal dampness. By ensuring breathability, the jacket helps mitigate this issue."

Being lightweight implies the fabric is thin, which often poses a risk of decreased durability.

"Unlike general trail runners, top runners like Dylan tend to wear jackets over their backpacks. Therefore, to enhance durability, we printed glass beads resin on areas that might wear easily, such as the back and front, where backpack adjusters tend to press against the fabric."

The Biggest Challenge Was Fitting

In contrast, we thoroughly eliminated anything that added weight.

For example, seam tape is crucial in waterproof jackets to prevent rain from seeping in, but we opted for lightweight, narrow tape.

"Using narrower tape means it needs to match the seams perfectly, which requires precision. The tape is also heat-activated for adhesion, but high temperatures can cause distortion on the outer side.

"Conversely, lowering the temperature to prevent distortion can weaken the adhesive strength. Our company has a tech lab dedicated to performance evaluation, where we researched optimal temperatures and duration for adherence without affecting the outside and established a proper bonding method."

Furthermore, we not only used ultra-fine rubber for the hood, cuffs, and hem but also paid special attention to their placement.

"Typically, hoods are designed to fit to the head with adjusters, but this jacket enhances the fit simply by integrating fine rubber along the sides of the face, ensuring the hood stays on even in wind.

"While adding drawcords or adjusters allows adjustment of a larger hood, we had to achieve a secure fit without those features, making fitting the most challenging aspect of the design process."

By surrounding the entire design with rubber, one can easily prevent rain from entering. However, through meticulous pattern scrutiny and repeated validations at the tech lab, we successfully developed a super lightweight jacket that boasts high waterproof performance without the need for extensive rubber usage.

Another focus of Dylan is "ease of movement."

The feedback on comfort encompasses details such as the shape when wearing the hood, the height of the placket, and the fact that it doesn’t hinder movement when worn over a backpack. The attention to comfort is extensive.

"First of all, seams can create a bad sensation on the skin. Therefore, instead of having seams typically located at the shoulders, we eliminated those and connected the front, sleeves, and back using a single piece of fabric, with seams only at the sides.

"Additionally, to ensure ample space even when wearing the jacket over a backpack, we designed it to be approximately one size larger than usual."

Other details include shaping the upper arm to facilitate arm movement and slightly positioning the sleeves towards the front, showcasing meticulous attention to detail.

"It’s said that 'God is in the details,' and our brand places great importance on incorporating functionality within minimalist designs. I believe this jacket truly offers a sense of comfort amidst simplicity."

Although this jacket was developed for top runners, there are plans to utilize the technology cultivated through this development to expand into items for general trail runners in the future. I look forward to seeing what comes next.