Washi

Washi originated in Japan around the 7th century, likely introduced from China via Korea, but it evolved into a distinctly Japanese craft. The earliest extant washi document is the Shōsōin repository in Nara, which holds paper from the 8th century.² Production involves harvesting the bark of kōzo, gampi, or mitsumata, steaming it, removing impurities, and beating the fibers into a slurry. The paper is then formed on a bamboo screen using a technique called nagashi-zuki, where a viscous mucilage from the tororo-aoi plant is added to slow drainage and align fibers. This method yields thin, strong sheets that are then pressed and dried on wooden boards.

Washi is not a single product but a family of papers distinguished by fiber and region. Kōzo paper is the strongest and most common, used for shoji screens and lanterns; gampi paper has a natural sheen and is prized for book restoration; mitsumata paper is fine and smooth, often used for banknotes and diplomas.³ Notable regional varieties include Echizen washi from Fukui Prefecture, Mino washi from Gifu, and Tosa washi from Kōchi, each with its own techniques and fiber blends. These regional styles are protected as traditional crafts under Japanese law.

Beyond traditional uses in calligraphy, ukiyo-e prints, and sliding doors, washi has found modern applications in conservation, fashion, and technology. Its long fibers make it ideal for repairing aged books and artworks, as seen in the restoration of European manuscripts.⁴ Washi is also used in the production of Japanese banknotes, which are noted for their durability and resistance to counterfeiting. Contemporary designers have incorporated washi into lighting, clothing, and even automotive interiors, while artists like Ayomi Yoshida have used washi in large-scale installations. Conservation efforts focus on sustaining the craft by training younger artisans and preserving the cultivation of fiber plants.

Washi has several surprising dimensions beyond its common uses. During the Edo period, washi was used as a form of currency in some domains, and it was also employed in making umbrellas, kites, and even armor components. The Shōsōin collection includes washi dyed with indigo and madder, showing early color techniques. A niche practice is kamisuki, the art of papermaking by hand, which is still taught in workshops in rural Japan. In the 20th century, washi was used in the Hiroshima Peace Memorial restoration, and it is also a component in some high-end audio speaker cones due to its acoustic properties.⁵ Additionally, washi has been used in space exploration—NASA used washi for the Stardust mission's dust collector, leveraging its strength and purity.⁶

Kōzo

Paper mulberry (Broussonetia papyrifera), the most common fiber source for washi.

Gampi

A shrub (Wikstroemia sikokiana) whose bark yields a lustrous, strong paper.

Mitsumata

Edgeworthia chrysantha, a plant producing fine, smooth fibers used in banknote paper.

Nagashi-zuki

A papermaking technique using a mucilage to suspend fibers and create thin, strong sheets.

Tororo-aoi

Abelmoschus manihot, the plant whose root mucilage is used in nagashi-zuki.