“Yunker” was first launched in Japan in tablet form in 1956. The first canned tablet form gained recognition amongst the middle-aged and elderly group
as a tonic. Wanting to develop a key product symbolizing Sato as a national provider of health products, Sato continued to strive to strengthen Yunker through research of natural herb-based liquid products.

In October 1967, 11 years after the birth of liquid Yunker, Sato launched “Yunker Kotei Solution”, an invigorating drink that was developed to improve human life by enhancing the formula of natural herbs. “Yunker Kotei Solution” steadily won loyal users as word-of-mouth spread of the unique product. Yunker became known as the staple product to recover from fatigue within the entertainment business with strong support from writers, comic artists and editors. When “Yunker Kotei Gold” was launched in 1977, it caught the attention of weekly magazines and TV shows which extended the growth of Yunker users.

The efficacy of Yunker was demonstrated scientifically in the 1980s to the 1990s. When Japan reached the zenith of its bubble economy, several competing products appeared on the market. Amidst cutthroat competition, Sato built the Shinagawa R&D Center in 1994. As a result, a series of Yunker products were introduced to provide solutions to various types of fatigue that afflict people today.

Sato has developed several solutions of Yunker since its birth 48 years ago to make it a world-famous product. Yunker has entered a new stage of development beginning with the introduction of Yunker Kotei Solution overseas in Fall of 2004. Sato hopes the uniform-formula drink becomes No.1 globally and attracts worldwide attention to the superior technology and originality that Sato provides.