1931年茨城県生まれ。東京教育大学教育学部芸術学科を卒業後、1953年に瑛九創設の「デモクラート美術家協会」に参加。1958年に渡米しニューヨークを拠点に活動。60年代から前衛芸術運動「フルクサス」に加わり様々なイベントを展開。レインボー絵画を多数制作する。また、版画も多数制作し、現代版画の代表作家としても有名。1966年ヴェネツィア・ビエンナーレ、1971年サンパウロ・ビエンナーレ日本代表として参加し、ブラジル銀行賞を受賞。1987年にはエッフェル塔に300mの虹の帯をかけるプロジェクトを実施。1995年に紫綬褒章を受章。

Born in Ibaraki Prefecture in 1931. After graduating from the Department of Art, Faculty of Education, Tokyo University of Education, he joined the Democratic Artists Association, founded by Ei-Q, in 1953. He moved to the United States in 1958 and based his activities in New York. In the 1960s, he joined the avant-garde art movement Fluxus and organized various events. He produced numerous rainbow paintings. He also produced numerous prints and is known as a leading contemporary printmaker. He represented Japan at the 1966 Venice Biennale and the 1971 São Paulo Biennale, where he won the Banco do Brasil Prize. In 1987, he carried out a project to drape a 300-meter rainbow ribbon around the Eiffel Tower. He was awarded the Medal with Purple Ribbon in 1995.