Report from the IFLA Asia PAC Centre – Conservation activities using washi
This is the first of an ongoing series of reports from the IFLA Preservation and Conservation (PAC) Centres regarding their activities and future work in their regions.
The National Diet Library of Japan (NDL) was designated the IFLA/PAC Regional Centre for Asia (PAC Asia) in 1989. PAC Asia was established in order to enhance awareness throughout Asia of the importance of preservation and conservation activities by distributing information, organizing training programs, and conducting other forms of research. Given that Asia is a vast area with a great variety of languages, cultures, and climates, PAC Asia’s task is no simple one, but it has endeavored to respond to as many of the various inquiries and requests it has received. In addition to dispatching experienced NDL staff members to give lectures throughout the region, it welcomes colleagues from other countries in Asia, and most recently hosted colleagues from Nepal as part of the PAC Asia’s contribution to reconstruction of libraries in Nepal.
Washi (traditional Japanese paper)
Conservation and restoration activities that utilize washi are a key part of PAC Asia’s expertise. The 1000-year-old history of washi craftsmanship was recognized in November 2014 with a place on UNESCO’s Representative List of the Intangible Cultural Heritage of Humanity. The majority of washi is made of Kozo (mulberry) fibers, and the washi used at the NDL is generally 100% Kozo. The paper fibers in washi are generally longer than those found in western paper. Kozo fibers are flexible, thin, durable, and often a full centimeter in length. This durability is what makes washi such a useful material for conservation activities. Washi’’s durability is demonstrated by extant historical documents made of washi that date back as far as the 8th to 11th centuries. This is proof that washi will last more than 1000 years, if properly preserved in a suitable environment.
The washi strip shown at the top of in Fig. 2 was moistened with water and torn by hand, while that at the bottom was cut using an edged blade. Washi is often torn by hand so that the edges will have long fiber extensions such as these. This “feathered edge” is what allows washi to bond firmly with an adjacent sheet of paper. The fiber extensions provide a greater surface area for increased adhesive strength.
There are many varieties of washi, and each comes in a range of different thicknesses. For conservation and preservation activities, we choose a suitable type of washi, depending on the condition of the materials to be repaired.
Repairing damaged pages with washi
Fig. 4 is of a diary written in the late 19th century on washi. The pages contained holes where insects had eaten their way through. To repair these pages, we first chose a piece of washi of thickness and texture similar to that used in the diary. Next, we tore off a piece of washi just a little larger than the hole, which we covered with washi, using starch paste to seal the gap. Once the holes were repaired, the book could be handled normally without difficulty.
Newsprint is fragile and prone to deterioration. We repair torn newsprint by applying tengujoshi to both sides of the damaged page. Tengujoshi is one of the thinnest varieties of washi, which is why it can be used to cover a torn page without hiding the information on the material, as shown in Fig. 6.
We chose a colored washi that best matched the color of the torn front cover, and mended the cover from both front and back, as shown in Fig. 7. Since washi is tough and flexible, it can be dyed and dried as shown in Fig. 8, by hanging sheets of washi just like laundry.
There are a great many ways that washi can be used to repair damaged material. PAC Asia is working to develop more techniques for repairing damaged material with washi, so that they can be shared with our Asian colleagues.
–Kaoru Oshima (Ms), Director, IFLA/PAC Regional Centre for Asia, National Diet Library, Tokyo (Japan)