Aobana-gami is a coloring material used in making the preliminary sketch for yuzen dyeing. It is made by dyeing washi (Japanese paper) with aobana , a kind of dayflower (Commelina communis L. var. hortensis Makino). It was produced in large amounts in the past but now its production is on the verge of disappearance. Recently, documentary films taken in 1963 and 1978 by Dr. Konoshima Masao, a scientist of natural medicine, on the production of aobana-gami were presented to the Department of Intangible Cultural Heritage. They serve as valuable material in preserving the techniques for the production of aobana-gami which are about to be lost today.