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89-yr-old Tokyo woman continues to invent, inspired by problems she faces in daily life

Mieko Sato holds the "Plastic bottle akeru-kun," which she invented 11 years ago, in Machida, Tokyo, on Nov. 24, 2022. (Mainichi/Shota Harumashi)

TOKYO -- An 89-year-old woman has shown that people don't necessarily need special knowledge or skills to start inventing -- by creating a hit product that now sells tens of thousands of units a year.

    Eleven years ago, Mieko Sato, a resident of Machida, Tokyo, created a tool to open plastic bottles using only a small amount of force. The rubber tool, named "Plastic bottle akeru-kun," is available at co-operative stores nationwide for 400 yen (about $3) per piece, and 30,000 to 40,000 of them are sold each year.

    While she is now advanced in years, Sato says with a smile, "I don't have time to die."

    The tool is made by hand by cutting a rubber tube into a 4-centimeter length, dyeing it, drilling holes in it, and threading a string through it.

    The inspiration for the product came when Sato felt her strength waning as she began having difficulty unscrewing the caps of plastic bottles. The prototype, which was made with a flat rubber band, prevented the lid from slipping, allowing it to be opened without much effort.

    This photo shows a tool named "Kanzume akeru-kun," created by Mieko Sato, in Machida, Tokyo, on Nov. 24, 2022. The tool makes it easy for people to open cans without hurting their hands or nails. (Mainichi/Shota Harumashi)

    After consulting with the Tokyo-based Hatsumei-gakkai, a general incorporated association that supports people who love inventions, Sato obtained a patent in 2011. She went through trial and error to finally commercialize the product in its current form, which is made from rubber tubing with a 2.8-centimeter diameter.

    In 2013, when Sato and her fellow inventors exhibited their products at a department store event, the plastic bottle openers sold so fast that she had to rush to make additional ones. She sold 280 of them in five days, using up all the materials she had prepared. This spring, she received a monthly order for 5,000 units, and she and her husband worked hard to fill it.

    "All you need to invent something is motivation and the ability to take action as soon as you hit upon an idea," said Sato. "I don't have the academic background or the skills, but it doesn't matter. It's worth it, knowing that my products are helping someone." Her approach indicates that the first step is to solve the inconveniences and problems people experience in their daily lives.

    Sato has also developed tools for opening jam jars and cans, and has recently been working to commercialize "zori slippers" -- slippers with geta straps attached.

    The Hatsumei-gakkai association has approximately 3,000 members who have made inventing their life's work, as well as 100 companies that hope to benefit from the assistance of these people. Although some members are former engineers, the majority are apparently amateurs, and many are senior citizens.

    The association receives consultations from members on commercialization, teaches them how to apply for patents and trademarks, and introduces them to small- and medium-sized companies with a variety of technologies, including metal and plastic processing and resin molding.

    (Japanese original by Shota Harumashi, Tokyo City News Department)

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