Kozo is a general name of the fiber taken from various types of mulberry plants that is utilized to make paper. Kozo is a principal fiber used in this Japanese paper and is known for its strength, flexibility and length. Traditional kozo paper is naturally colored and made from 100% kozo fiber. Kozo paper has 4 deckled edges and is white and acid free. It also has smaller pores. The name goyu is sometimes used for the heavier variety of kozo.

It is prepared without chlorine bleaching, with carefully prepared fibers; these papers are strong, translucent, malleable, warm to the touch and absorbent. They are beautiful and have slightly textured surfaces. It is this multiplicity of characteristics that offers potential like no other medium. The excitement of the prints comes from exploration of these qualities, often a long journey that results in truly unique expression. They have good absorbency even when very thick because the careful preparation of the fiber creates an even receptivity to ink and moisture.