The Four Kashio Brothers | CASIO

The Four Kashio Brothers

The unique strengths of four people, united as one

Casio was founded by the four Kashio brothers: Tadao, Toshio, Kazuo, and Yukio.
Led by the second eldest, Toshio, the four brothers developed the 14-A, the world’s first compact all-electric calculator, and established Casio Computer Co., Ltd. in 1957. Each brother brought his unique specialty and strength: Tadao in finance, Toshio in development, Kazuo in sales, and Yukio in production. Taking on a specific role and working closely to complement each other, the brothers grew the new company together.

Tadao Kashio
Tadao Kashio

May 1960- December 1988
The leader who built Casio on trust and collaboration

Tadao Kashio 1917-1993
As the eldest of the four Kashio brothers, Tadao served as the Casio leader from its inception, laying the groundwork for Casio Computer Co., Ltd.

Tadao Kashio was originally employed as a lathe operator at a factory, putting to use the metal processing techniques that he learned at Waseda Koshu Gakko (now Waseda University). The factory owner recognized his skills, and he was given charge over factory operations, later leaving to go into business on his own. In 1946, he formed Kashio Seisakujo, a manufacturer of machinery parts. His brother Toshio joined him first, followed by Kazuo and Yukio, and the four brothers soon began work on developing their calculator.

After establishing Casio Computer Co., Ltd, the brothers’ father, Shigeru, served as the company’s first president, with Tadao later succeeding him to become the company’s second president in 1960. Although originally an engineer, he embraced his role as leader, studying finance, bringing Casio together under solid management, and serving as president for 29 years until 1988.

Tadao Kashio
Toshio Kashio
Toshio Kashio

December 1988 - June 2011
The innovator whose work with digital technology created “something from nothing” over and over again

Toshio Kashio 1925-2012
Toshio Kashio was an inventor who used digital technology to come up with products that would change the world. He was the developer behind the original calculator, watch, and electronic musical instrument that would form the core businesses of Casio Computer Co., Ltd.

Having read Edison’s biography at the age of six, Toshio always wanted to become an inventor. He studied digital technology by learning about light electrical currents at the electrical engineering school (now Tokyo Denki University) and working as a communications engineer for the Ministry of Communications. Quitting his job with the Ministry to devote himself to his inventions, he joined Kashio Seisakujo, the business that his brother Tadao had formed. Focusing on the potential of calculators, he invented the 14-A, the world’s first compact all-electric calculator small enough to be used in an office setting. He later employed digital technologies in developing the CASIOTRON, the world’s first digital wristwatch with an automatic calendar, which would introduce Casio as a watch manufacturer. His focus on the question of what sound is led to the development of Casio electronic musical instruments. Toshio utilized digital technology to create information devices that would change people’s lives, and, as head of Casio development, he delivered new products to people the world over.

Toshio Kashio
Kazuo Kashio
Kazuo Kashio

December 1988- June 2015
President and CEO
June 2015- June 2018
Chairman and CEO
The market-maker whose innovative ideas and ability to get things done created a digital culture

Kazuo Kashio 1929-2018
With an originality unhampered by conventional ideas, a foresight into market trends, a strong will, and the ability to get things done, Kazuo Kashio brought digital information devices designed for anyone to use into the lives of people far and wide.

Initially responsible for production when the company was founded, Kazuo later took charge of sales and marketing. Through his experiences in the market and dealing with competition from rival companies, he gained a clear understanding of the importance of product appeal and put this to work in product planning. He led the development of the Casio Mini, the personal calculator launched in 1972 that brought the calculator to the consumer market. Positioning the G-SHOCK shock-resistant watch as a mainstay of the market, he helped turn the conventional view of the wristwatch as a “fragile, luxury item” on its head, leading the way for watches to play a role in many more scenarios. In 1995, Kazuo took the lead on the launch of the QV-10 digital camera, laying the groundwork for the image-based communication age. His highly original product planning always sought to create entirely new markets. His passion was creating useful products that improved people’s lives and helped them learn, and this focus informed his 27 years in management as the company’s third president. Kazuo developed the company to the Casio we know today, building on the foundation laid by his brother and previous president Tadao.

Kazuo Kashio
Yukio Kashio
Yukio Kashio

May 1996- June 2014
Executive Vice President
The engineer who strengthened the design and production technology at the core of Casio craftsmanship

Yukio Kashio 1930-
As an engineer, Yukio Kashio was the one who brought designs for added quality and mass production technologies to the products invented by his brother, Toshio.

Yukio, who studied design at university, joined Kashio Seisakujo to work on the development of Casio calculators. He took charge of drawing up the digital circuitry proposed by Toshio, creating the designs that would be turned into actual products. He also developed technologies to make the product easier to use, including improvements in circuit implementation for the Casio Mini and proposals for simple mechanisms that helped keep the price down to 10,000 yen.

Becoming head of production in 1965, he launched a fully automated production line for calculators, built numerous production plants, and helped Casio achieve mass production. The structure that Yukio Kashio built has become the foundation of the Casio production network today, one which currently produces 100 million products every year and delivers reliable, high-quality products to people around the world.

Yukio Kashio

│Origin of the company emblem

The company emblem is a design that encompasses and highlights the Casio trademark with a circle of four Ks, the initial letter in Kashio. The emblem symbolizes the strong ties among the four Kashio brothers that founded and developed their calculator business. Toshio Kashio, inventor of the Casio calculator, designed the emblem himself to embody their approach to the business.



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