Koko Hayashi never forgot the day her friend asked why her grandmother smelled strange. Koko was a child at the time, living with her family in Japan, and didn’t know how to respond. She loved her grandmother, who was always clean and careful with her appearance. But there was a distinct smell that Koko hadn’t noticed before. It wasn’t sweat or dirt. It was just different. Years later, Koko found out it wasn’t unusual. Japanese researchers had identified a specific odor that forms on aging skin. They called it Nonenal.
Nonenal develops as the skin’s natural oils break down over time. It can’t be washed away with regular soap because it’s fat-soluble, not water-soluble. Koko learned that Japanese persimmon extract could neutralize it. In Japan, soaps containing persimmon were already popular among older adults. But when she looked for a similar product in the United States, she found nothing. She kept thinking about that moment from her childhood — how embarrassed she had felt on behalf of her grandmother — and realized she could make a difference for people who might feel the same way.
Koko decided to bring the concept to the U.S. In 2014, she founded Mirai Clinical. The name means “future” in Japanese, reflecting her goal of helping people age with dignity. She moved from Japan to California, leaving behind her stable job to focus on the new business. At first, she imported small batches of Japanese persimmon soap to test the market. It wasn’t easy. Few people in the U.S. had heard of Nonenal, and it took a lot of explaining. Early sales were slow, and Koko considered giving up more than once.
One day, a Japanese news outlet picked up her story. Suddenly, Koko found herself flooded with orders from Japanese Americans who knew about the problem and wanted a solution. That brief surge proved that the market existed. Still, building a consistent customer base took years. Koko kept refining the products and learning how to reach people who needed them. She wanted to make sure the soaps were not only effective but also pleasant to use.
The core of the line remains the persimmon deodorizing soap. It’s made by hand in Osaka, using high-quality persimmon extract sourced from family-owned farms. The soap itself is shaped like a round puck, easy to hold and use, and lathers into a light, clean foam. The goal is to remove the compounds that cause aging odor without harsh chemicals. Over time, Koko added more products to the lineup: a persimmon body wash, natural deodorant sticks, body wipes, and even a sweat test kit that helps detect Nonenal levels. The brand’s focus stayed consistent — practical hygiene products for older adults that help them feel fresh and confident.
Koko never wanted Mirai Clinical to feel like a luxury brand. She aimed for simplicity and accessibility, offering straightforward products without gimmicks. The company grew gradually, mostly through word of mouth and online sales. During the pandemic, when other companies struggled, Mirai’s direct-to-consumer model held steady. Older customers appreciated being able to order hygiene essentials without leaving home. Koko also built a subscription model to make reordering easy, especially for customers who needed a steady supply.
As more people discovered the brand, it became clear that Mirai wasn’t just about solving a problem. It was about respecting the way people age. Koko’s mission has always been rooted in her own experience — seeing her grandmother feel self-conscious, then realizing later that it wasn’t just her. It was something that happens naturally as people get older. She wanted to take the shame out of it.
Today, Mirai Clinical has expanded beyond just soap. The product line includes body washes, deodorant sticks, and travel-sized items. Koko still oversees the product development, making sure each item meets the original goal — keeping people comfortable and confident. She says that whenever someone writes to thank her for making them feel better about themselves, it reminds her of why she started. It wasn’t just about creating a product. It was about changing how people feel about aging.
