INTERVIEW | 'pure blue japan' CEO Iwaya On His Passion for Denim

Japan is renowned for its craftsmanship and attention to detail, and denim is no exception. Celebrated worldwide for its quality, durability, and unique fading patterns, Japanese denim has carved out a special place in the global fashion scene. JAPAN Forward heads to Tokyo's Harajuku district to speak with Ken-ichi Iwaya, the chief executive officer of the internationally acclaimed brand, pure blue japan®.

In a two-part interview, Iwaya discusses the art, tradition, and innovation behind this iconic industry and his brand. Excerpts follow.

From Okayama to the World

*pure blue japan® shop in Harajuku, Tokyo. (©JAPAN Forward)*

Can you tell us about the history of pure blue japan®?

Before I started this business, I worked at a textile company in Okayama. Our customers included denim manufacturers.

I thought, "I want to try making jeans myself," but I had no background in fashion. Making clothes was much harder than I expected. But I already knew about fabrics from my job and also had connections with fabric manufacturers.

It was a spur-of-the-moment decision to start the business. But back in 1997 there was minimal accessibility to the internet. The only way to sell products was through Tokyo. So, I quit my job and moved to Tokyo. I started small, working out of a tiny apartment. I had always loved this particular building (in Harajuku) and wanted to set up shop here.

When did you start selling your jeans internationally?

Fifteen years ago, a new category for Japanese denim was finally recognized in the global fashion industry. Around that time, the owners of a new store called Blue in Green in SoHo New York offered to sell our jeans.

Once they started selling our jeans, we saw the power of New York's media. After our products entered that store, we never had to do sales outreach again. Offers from all over the world just started coming in.

*Jeans in the window of pure blue japan® shop in Harajuku, Tokyo. The jeans demonstrate how indigo dye fades over time. (©JAPAN Forward)*

Why is Japan so strongly associated with denim today?

Jeans originated in America. The fabric used back then was woven on narrow looms. "Selvage denim" comes from that era. Over time, wider looms were developed to increase efficiency, and the older looms were discarded. However, Japan kept those old looms. As a result, Japan became one of the only places where the original selvage denim could still be made.

Another point is that indigo dyeing requires water that interacts well with the dye. Japan's water quality turns out to be ideal for this. Most fabrics are dyed so the color won't fade, but denim is intentionally dyed to fade over time. The indigo dye only penetrates the outer layer of the yarn. As the jeans are worn and washed, the blue outer layer fades, revealing the white core, which creates that distinctive fade pattern.

Wearing a Unique Story

People love denim because each pair tells a unique story — bikers get faded on the seat, while workers who kneel a lot get faded knees. Japan excels at this dyeing process, creating fabrics that fade beautifully.

You'll notice a rough texture when you touch our jeans. That's another aspect of Japanese craftsmanship. We modify the weaving machines to create this texture. Japan's meticulous craftsmanship also extends to denim.

Weaving Perfection

*pure blue japan® shop in Harajuku, Tokyo, where various product show the progressive fading of indigo dye over time. (©JAPAN Forward)*

What is the production process like?

Some brands own their own factories, but we deliberately chose not to. Instead, we decided to work with professional factories. The factories we work with specialize in denim production, and it would be impossible for us to surpass their level of craftsmanship. So, rather than trying to compete, we entrust production to them. That said, we don't work with just any factory. It took about ten years to find the right one.

We tested various manufacturers. Denim comes in various thicknesses, and different machines are needed depending on the fabric weight. We had a specific stitching style in mind, which required specific equipment.

Industrial sewing machines are expensive — one can cost anywhere from ¥1-2 million JPY ($6,800-13,500 USD). No factory would invest in new machines just for us. So, we bought the machines ourselves and placed them in the factory. And we were able to achieve the exact product quality we wanted.

What is the design inspiration behind pure blue japan®?

Our company is called Syoaiya®. In Japan, "shoai" means true love, and we wanted to reflect that in our name. A lot of companies in our industry have Western-sounding names, so we intentionally chose kanji for ourselves.

From the beginning, I wanted to sell overseas, so we also created a brand called pure blue japan®. The logo is inspired by the indigo plant. The dots on the logo represent the selvage edge of denim fabric.

In terms of design, jeans have a set structure — two back pockets, front pockets — those details are fixed. We adjust them by making them slimmer or wider, raising or lowering the waistline. We're just refining what already exists.

How long did it take to research and achieve the perfect pure blue japan® jeans?

If we release a product and get a great response, we might use the same production method again, but we won't make the exact same item. Instead, we'll improve the design, change the color, or tweak some elements based on customer reactions.

We aim to create uniquely Japanese jeans — something with a special texture that can't be found elsewhere. But even with great ideas, there are practical limitations.

Sometimes, when discussing ideas with professionals, they'll say, "I understand what you're trying to do, but it's probably physically impossible." Or "That type of yarn just doesn't exist." Other times, they might say, "It might be possible, but we won't know unless we try."

But testing fabric designs costs millions of yen. So when we propose an experiment, manufacturers ask, "Are you really willing to take that risk?" And we just go for it.

That's how we're constantly pushing boundaries — trying to create denim that no one has ever seen or touched before. So, the research never stops.