washiJune 25, 2026

Tosa Washi

Tosa Washi (土佐和紙) is a washi produced in Kochi Prefecture (formerly Tosa Province), designated as a Traditional Craft Product by the Minister of Economy, Trade and Industry on December 25, 1976. It is counted among the three great washi papers of Japan alongside Echizen Washi of Fukui Prefecture and Mino Washi of Gifu Prefecture. In the strict sense, Tosa Washi refers to handmade washi produced using either the nagashi-zuki or tame-zuki technique, as designated under the Act on the Promotion of Traditional Craft Industries.

History

The earliest documentary record of Tosa paper appears in the Engishiki, a compilation of government regulations completed in 927. Papermaking in Shikoku is traditionally traced to the Awa Imbe clan and the transmission of papermaking techniques to Japan in the early 7th century. The craft became more widely known from the end of the medieval period through the early modern period.

Several events shaped regional papermaking traditions in Tosa. In 1569, Aki Saburo Saemon Ietomo, the second son of Aki Castle lord Aki Kunitora, fled to Awa Province when Aki Castle was attacked and destroyed by Chosokabe Motochika. In 1580, Nawakawa Castle lord Nawakawa Genba Kiyomune was also destroyed by Motochika. Around 1596, a traveler named Shinojo from Hyuga-tani village in Iyo Province taught papermaking techniques — specifically the method for making Shuzenji paper — to Yoho and Ietomo after they nursed him back to health. Senkashi, a paper noted for its strength, was developed in 1587 by Doi Taro Zaemon Michimasa, who retired and took the pen name "Senka."

The poet Ki no Tsurayuki, during his appointment as provincial governor, is said to have encouraged papermaking in Kureta village, leading to production there. In 1852, local resident Takamura Tsuneshiro introduced papermaking techniques to Kureta, and the tradition reached its peak from the late Meiji to Taisho era. In 2008, the last successor of Kureta-gami died, severing that tradition.

From the Edo period, Tosa Washi was known as one of the "Tosa Sanpaku" — the three white products of Tosa — alongside Tosa lime plaster and raw silk, and was shipped nationwide. In 1785, an "Ikegawa Paper Revolt" occurred when a merchant named Kyoya Tsunesuke became a domain-designated merchant and bought paper cheaply, prompting craftsmen to attempt to flee to Iyo. Susaki Hanshi, produced by farmers in the Shinjo River basin of Tsuno Town and shipped to Osaka and Tokyo, peaked from the Meiji teens to the early Taisho era.

Tosa Tengujo-shi, a notably thin paper, was originally made in Gujo, Mino Province (present-day Gifu Prefecture) since the Kyoroku era and was introduced to Kochi in 1880 by Yoshii Genta, a papermaking improvement technician of Ino Town. The Tosa Tengujo-shi Preservation Society was established in 1972, and in 1973 the paper was selected as an Intangible Cultural Property requiring documentation. In 1976, educator and chigiri-e artist Kamei Kenzo discovered that Tosa Tengujo-shi was suitable for expressing tones of light and shade in chigiri-e art. Hamada Yukio, a technique successor of Tosa Tengujo-shi, was designated as a Living National Treasure in 2001.

In 2009, papermaking in Kuroshio Town was revived for the first time in 50 years by a woman who had moved from Tokyo. During World War II, Tosa Washi was used militarily as material for balloon bombs (Fu-Go). A factory in Asahi-cho, Kochi City had produced typewriter paper for export before the war. Kochi Prefecture supplied approximately 40% of the washi used in the 9,300 balloon bombs launched between November 1944 and April 1945, according to former Ehime Prefecture Paper Research Institute director Maemitsu Rikuro. Some of these bombs crossed the Pacific and reached the continental United States, where civilians hiking in Oregon were killed in an explosion.

Tosa Washi technology later developed into modern functional papers, including condenser paper by Nippon Kodoshi Industries, ultra-thin polyester fiber paper by Hirose Paper Manufacturing, and tea bag base paper by Nankoku Pulp Industry and Nihon Shigyo.

Techniques & Production Process

Tosa Washi is produced using two traditional hand-papermaking methods: nagashi-zuki and tame-zuki. The primary fiber materials are kozo (paper mulberry), mitsumata, and ganpi. As of the most recent available data, 22% of the kozo used was domestically sourced while 78% came from overseas, mainly Thailand. Mitsumata usage was 44% from Kochi Prefecture (85 kg) and 56% from overseas (110 kg). Ganpi usage was 14% from Kochi Prefecture (200 kg), 2% from other domestic prefectures (30 kg), and 84% from overseas (1,205 kg).

As a dispersing agent (neri) in the papermaking process, tororo-aoi accounted for 65% (452 kg) of usage, while the remaining 35% (246 kg) used chemical paste. Tosa Tengujo-shi specifically uses the abundant water of the Niyodo River and red kozo grown in its basin as raw materials. Tosa Seicho-shi is made from red kozo using kaya (miscanthus) screens, while Tosa Usuyou Ganpi-shi, uniquely among the five prefecture-designated intangible cultural property washi types, uses ganpi (Diplomorpha sikokiana) rather than kozo, and employs gauze-woven screens instead of bamboo screens.

Senkashi achieves its characteristic strength through a manufacturing method of bonding two sheets of paper together. During World War II, balloon bomb paper was processed with sodium carbonate for alkaline strengthening, then glycerin-treated for flexibility before drying, yielding a transparent leather-like paper. Technically, Tosa Tengujo-shi can be made as thin as approximately 5 g/m², considered the limit for handmade paper due to constraints from cellulose fiber thickness. Ino Town in Agawa District, adjacent to the west of Kochi City, is recognized as one of the prefecture's leading paper-producing towns.

How to Identify Tosa Washi

The various paper types within the Tosa Washi category are distinguished by their fiber composition, screen type, and physical properties. Tosa Tengujo-shi is characterized by its exceptional thinness, described as resembling "the wings of a mayfly." It has a standard basis weight of 12.9 g/m² and a minimum thickness of 0.03 mm. Hidaka Washi Co., Ltd. in Hidaka Village produces machine-made Tengujo-shi at 2 g/m² and 0.02 mm, used for books and cultural property restoration. Tosa Seicho-shi is associated with use as daifuku-cho (account books), temple death registers, and woodblock print paper. Tosa Usuyou Ganpi-shi is identified by its use of ganpi fiber and gauze-woven screens, distinguishing it from the kozo-based papers in the Tosa Washi family. Tosa Shichishikishi (seven-colored paper of Naruyama) is dyed in subtle colors using yamaomo, suou, kuchinashi, and ai plants.

The Craft Today

Handmade washi production in Kochi Prefecture peaked at 2,305 tons in 1953 and had declined to only 13 tons by 2005. As of 2018, members of the Kochi Prefecture Handmade Washi Cooperative included 7 households in Ino Town, 8 in Tosa City, and 1 each in Niyodogawa Town, Kuroshio Town, and Tsuno Town. In 2018, Kochi Prefecture's tracked domestic kozo production was 6,518 kg, of which 123 kg was sold outside the prefecture, with an additional 10,442 kg produced through contract farming not captured by official figures.

Of the five washi types designated as Kochi Prefecture Intangible Cultural Properties in 1980 — Tosa Tengujo-shi, Tosa Seicho-shi, Susaki Hanshi, Kariyama Shoji-shi, and Tosa Usuyou Ganpi-shi — only two (Tosa Tengujo-shi and Tosa Seicho-shi) remain in production, each by a single producer. At its peak, Tosa Tengujo-shi was produced by 200 households in former Ino Town and Hidaka Village. The only person in Kochi Prefecture currently capable of making all types of sukigeta (papermaking frames) is reported to be one elderly craftsman. Senkashi is produced in Shimanto Town, one of three domestic production sites alongside Seiyo City (former Nomura Town) and Kihoku Town in Ehime Prefecture. Tissue paper and non-woven fabrics produced in Kochi Prefecture are referred to as "Tosa Gami" and are positioned as products derived from the washi tradition.

For broader context on Japanese washi paper traditions across Japan, including related regional papers such as Awa Washi from neighboring Tokushima and Ozu Washi from Ehime Prefecture, those articles provide additional comparative information.

Frequently Asked Questions

What makes Tosa Washi different from other Japanese washi papers?

Tosa Washi is counted among the three great washi papers of Japan, alongside Echizen Washi and Mino Washi. It encompasses a range of paper types with distinct characteristics, from the extremely thin Tosa Tengujo-shi — with a standard basis weight of 12.9 g/m² and a minimum thickness of 0.03 mm — to the double-layered, strength-focused Senkashi.

When was Tosa Washi designated as a Traditional Craft?

Tosa Washi was designated as a Traditional Craft Product by the Minister of Economy, Trade and Industry on December 25, 1976.

What raw materials are used to make Tosa Washi?

The primary fiber materials are kozo, mitsumata, and ganpi. The proportion of domestically sourced materials varies by fiber: 22% of kozo, 44% of mitsumata, and 14% of ganpi used in Tosa Washi production comes from Kochi Prefecture. Tororo-aoi serves as the natural dispersing agent (neri) in 65% of production, with chemical paste used for the remainder.

How has Tosa Washi production changed over time?

Handmade washi production in Kochi peaked at 2,305 tons in 1953 and declined to 13 tons by 2005. As of 2018, the Kochi Prefecture Handmade Washi Cooperative had members in five towns, and of five washi types designated as prefectural intangible cultural properties in 1980, only two remain in production, each by a single producer.

What is Tosa Tengujo-shi and why is it significant?

Tosa Tengujo-shi is a type of extremely thin kozo paper introduced to Kochi in 1880 by Yoshii Genta of Ino Town. It is characterized by its thinness, described as resembling "the wings of a mayfly," with a standard basis weight of 12.9 g/m². The Tosa Tengujo-shi Preservation Society was established in 1972, and Hamada Yukio, a technique successor, was designated as a Living National Treasure in 2001.

Are there other washi papers from the Shikoku region?

Yes. Awa Washi from Tokushima Prefecture received its Traditional Craft Product designation on the same day as Tosa Washi, December 25, 1976. Ozu Washi from Ehime Prefecture received its designation on October 21, 1977. Awa Washi in Shikoku is also historically connected to Tosa papermaking, as the Awa Imbe clan is cited as the origin of papermaking in the region.