He has created many excellent works. Tomo Katou used a very dark black “sumi” (ink) on silk. This secret technique was handed down by Kibou Kodama (his master 1898-1971) to him. Even Genjin Sugihara (1912-2009), who was Katou’s senior fellow disciple, couldn’t learn it. Painters who can use this technique effectively are rare in the contemporary Japanese-style painting world. It is the reason that Tomo Katou’s suiboku-ga on silk are highly regarded.