Oyanagi

…Although it was often simply called “Yanagi,” this name was also the name of the brewery, and was apparently due to the use of willow wood for the barrels. In the Bunmei era (1469-87), some businesses began to use the name “Yanagi” for fame, so the business name was changed to “Oyanagi” (Oyanagi Sake Shop) and the six-star crest was added to the barrels. This was the beginning of sake brands. …

*Some of the terminology that mentions "Oyanagi" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…たんに〈柳〉とだけ呼ばれることが多かったが，この名は醸造元の屋号でもあり，樽材に柳の木を用いたのにもよるらしい。名声のために文明年間(1469‐87)には〈柳〉の名を盗用する業者も出現したので，屋号を〈大柳（おおやなぎ）(大柳酒屋)〉と称し，樽に六曜(六星)紋を付した。これが酒の銘柄のさきがけとなった。…

※「大柳」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報