One of the original members of Gutai Art Association since its establishment. Above all, the art of Shimamoto is characterized by its huge-scale dynamism. Shimamoto is internationally recognized by his cannon painting which is using his handmade cannon to shoot color balls and by his bottle-throwing paintings, which he uses the bottle filled with paints. Essence of the art of SHimamoto, which can be said as "the trace of action" itself, embodies the spirit of GUTAI most clearly and contributes to attract international attention for Japanese contemporary art. Also the artist is not the last to focus on Mail Art. Thus, Shimamoto never stops to be a pioneer.