Kurobane Aizome: Developed as Workwear for Nakagawa River Lumber Merchants

About a 20-minute bus ride from Nasushiobara Station in Tochigi Prefecture brings you to Kurobane Aizome Konya in the Kurobane district of Otawara. At the entrance to the storehouse, an indigo noren (curtain) dyed with the shop's crest, “Te,” flutters in the wind.

“This year marks our 222nd anniversary. I'm the eighth generation to run this indigo dyeing workshop, which dates back to the Edo period. This area once prospered as a castle town for Kurobane Castle, and there were many lumber merchants who transported wood down the nearby Nakagawa River to Edo. While indigo dyeing is often associated with clothing for farmers, Kurobane Aizome was the workwear of merchants.”

Merchants would commission indigo-dyed hanten coats with their shop crests. It is said that the more layers they wore, the more it demonstrated the prosperity of their business, leading artisans to compete in making them.

“Since Kurobane Aizome was for workwear, it's characterized by its durable fabric and deep, rich indigo color. By first applying a base coat using a technique called shoen-zome—a liquid made from the soot of burnt pine roots, animal glue, and soybean juice—the fabric becomes stronger and can be dyed a deep, intense, dark color.”

Then, using a paste made from cooked rice bran and rice flour, patterns are applied with Ise-katagami (stencils). When the paste-applied fabric is indigo-dyed, beautiful patterns emerge where the white contrasts with the indigo.

“Although we incorporate some synthetic materials, the dyeing methods and raw materials from the Edo period have remained almost unchanged. We make our own paste, and we use the same indigo vats (aigame) that have been passed down for 200 years to prepare the natural indigo dye.”

There were originally five indigo dyeing workshops (konya) in the Kurobane area. As lifestyles changed with the times—for example, lumber merchants stopped wearing hanten—the workshops gradually went out of business.

“Faced with various challenges, including succession issues, our shop is the only one that remains today. We've managed to survive to the present day by creating different indigo products that reflect the times—from banners and noren in my predecessor's generation to apparel in my own.”

My Harsh Apprenticeship: "If You Don't Get It in a Year, Don't Bother Coming Back"

Ever since he can remember, Onuma's grandfather told him, "You'll take over the dyeing business." But he says the idea never really clicked. It wasn't until his third year of high school, when he had to decide his future, that he chose to join the family business.

"I didn't want to go to school, and I didn't want to get a job. The more I thought about it, the more I figured I should just work at home. That way, I could work whenever I wanted and hang out with my friends freely. It sounded like a dream. Looking back, I was so naive," he laughs.

However, the unexpected happened. After high school, he found himself training at a stencil-dyeing workshop in Tokyo. His predecessor, who had become a craftsman by teaching himself indigo dyeing after working in a kimono shop, wanted his son to learn the proper techniques and sent him away to train.

"The master at the workshop was incredibly strict. When I said, 'I look forward to working with you,' his very first words were, 'If you can't make it in the next year, don't bother coming back. If you can't master this in 10 years, just give up on this world.'"

For the first month, he just practiced flipping a spatula on a blank board, over and over like a batter practicing a swing. The next month, he did the same, but with resist paste on the board. Having just graduated high school, Onuma recalls that the painstaking training was agonizing every single day.

"It was so tough I wanted to quit, but my predecessor hated it when people didn't do things the right way. He was the type to say, 'If you quit, you're out of the house.' So, I couldn't bring myself to say how hard it was. I was caught between a rock and a hard place.

Nineteen is supposed to be the best time of your life, right? One day, some old classmates from my hometown teased me about my apprenticeship, and I was so frustrated. I'm competitive, so I used that feeling to push myself, thinking, 'Just you wait. I'll show you all and make you eat your words.'"

He gritted his teeth and endured the training. A year later, he could handle a decent amount of the dyeing process. He then returned to Tochigi and, after a period of helping the family business while commuting to Tokyo on the first train, he took over the company at the age of 24.

"My predecessor passed away suddenly. But by that time, I could handle most things on my own. It made me realize just how strictly he had taught me and how much effort he put into training me. I also became mentally tougher and don't get fazed by much anymore. Now, I'm just truly grateful."

A Path Forged by the Vow to "Only Make What I Love"

His predecessor, who transitioned from a kimono shop to a craftsman, was also an excellent salesman who had grown the small dyeing business into a large workshop. After his passing, major orders dwindled, and Onuma says there were some very tough times.

"There were tough times when sales dropped so much that I wondered if I could even make a living. That's when I decided that if the business was going to fail, I'd rather go down doing what I love. It would be easier to accept."

His predecessor had often made commemorative gifts like framed art and signature boards, as well as noren curtains for shopfronts. But looking at future demand, Onuma knew he needed to create something more eye-catching. Tapping into his interest in fashion—fueled by trips to Harajuku during his student days—he decided to create indigo-dyed sneakers.

"I modified the resist paste used for stencil dyeing and developed a runnier, liquid version. Instead of applying patterns with a stencil, I can now splash the paste onto the fabric with a brush, like paint. This technique allows me to add patterns even to sneakers."

Unlike traditional stencil dyeing where the paste is spread thinly with a flat brush, this splashed paste cracks as it dries. When the item is indigo-dyed, these cracks create unique, chance movements—variations in shade and bleeding—reminiscent of action painting in abstract art. He has used this method, among others, to create a range of indigo products, from small accessories to clothing.

"Making things that I personally want is what's important to me. I sometimes get requests like, 'You should make this, it'll sell,' but I won't make anything I don't love. That's a core belief I still hold firmly to this day."

As an 'Un-Artisan-Like' Artisan, I Want to Collaborate with a Variety of People

Kurobane Aizome Konya has also repeatedly collaborated with companies. It all started with a request from Hoshino Resorts' 'Kai Kinugawa.' For their 'Tochigi Mingei Room' concept, he adorned the bed runners and fusuma sliding doors of all 48 guest rooms with indigo-dyed fabric.

'The response was incredible,' he says. 'The best part was hearing people close to me say, "That's amazing." It was a moment where all the hard work from my younger training days felt completely worth it.'

From that point on, Kurobane Aizome became sought after for a wide array of spaces, including a hospital room, VIP lounges in sports facilities like stadiums, and corridors in public buildings.

'I truly believe the color of Kurobane Aizome is one-of-a-kind,' he explains. 'It would be fascinating to work with all sorts of unexpected people—the kind that make you wonder, "Where did they even come from?" My goal for the future is to share the magic of Kurobane Aizome through these collaborations.'

We asked Konuma, who is always taking on new collaborations, about his ideal image of an artisan.

'My ideal is to be an artisan who doesn't act like one,' he admits. 'People imagine artisans to be quiet and rigid, proud of their skills, and extremely particular. But you can't really approach someone who's standing there with their arms crossed, right? I'm a little shy, so it's not always easy, but my ideal is to be an approachable artisan that anyone feels comfortable consulting.'

To wrap up, here's an anecdote that perfectly captures Konuma's spirit as an 'un-artisan-like' artisan. For 15 years, he has been teaching indigo dyeing to local middle school students. He reportedly uses everything from homemade flip charts to references from anime and popular comedians' gags to make his classes engaging.

'The kids rarely laugh at my best jokes, but the teachers always do,' he admits with a smile. 'In an age where traditional crafts are fading, I believe the most important thing is to spark interest. Even if they forget the technical details, I want them to grow up and remember, 'Hey, indigo dyeing was fun.' That's the entry point I want to create.'

On the car ride back, Konuma mentioned that the Kurobane region is the hometown of Chika Ozeki, the protagonist of the NHK morning drama set for spring 2026, "風、薫る." As he spoke with excitement about his plans to sell indigo-dyed products in collaboration with "風、薫る", I was struck by a strong conviction: it's unconventional artisans like him who will shape the future.