| Born the eldest son of Chõnyu , he succeeded as the 8th generation il 1762 and went into
retirement in 1770, calling himself Sahei.
The name, Tokunyu, was given at the 25th anniversary of his death. being costitutionally weak, he retired when he was only 25 and died of illness four years later.
Only a few examples of his work remain, which all were made in his youth before the age of 25. He never managed to estabilish his own style and the influence of his father, Chõnyu, is prevalent in his work. He seems to have continued using the lustrous jet black glaze used by his father. Some of his tea bowls, however, are endowed with freshness and innocent charm.