| ■Tokyo National Research
Institute for Cultural Properties |
■Center for Conservation
Science |
| ■Department of Art Research,
Archives and Information Systems |
■Japan Center for
International Cooperation in Conservation |
| ■Department of Intangible
Cultural Heritage |
|
Survey of brush making
Lecture at Fudenosato Kobo
Although a wide range of tools and raw materials are used in the preservation and restoration of cultural property, fine arts, and crafts, many are at risk of being discontinued in the future due to a lack of skilled successors and increasing difficulty in securing the necessary materials. In response to this situation, the Center for Conservation Science, Department of Intangible Cultural Heritage and Department of Art Research, Archives and Information Systems at Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been involved in commissioned research on “Investigation of Tools and Materials Used for the Preservation and Restoration of Fine Arts and Crafts” as part of the project of the Agency for Cultural Affairs, “Support for the Management of Tools and Materials Used for the Preservation and Restoration of Fine Arts and Crafts.” This article introduces a field survey of brush making in Kumanocho, Hiroshima, held on October 21, 2025.
Brushes have been used for a long time traditionally in Japan as tools of painting and drawing, as well as for the preservation and restoration of cultural property. Makiefude brushes in particular are used for the preservation and restoration of lacquerware crafts, and there are not many craft artisans who can make them. For the project to reproduce the Hatsune Furnishings from the Tokugawa Art Museum’s Collection, brushes that could faithfully reproduce the intricate and exquisite techniques were needed.
For this survey, we visited Fudenosato Kobo and Hakuhodo Company, Limited. We were able to gain an overview of the history and techniques of making brushes in Kumano. A craft artisan carefully removed any hair that was damaged or facing the wrong direction at each step in the brush-making process and selected suitable hairs from a variety of types with diverse characteristics to produce the best possible brushes for a user. On observing this, we gained appreciation for the effort of craft artisans.
Like other traditional techniques, the brush-making industry also faces difficulties in procuring tools and raw materials. For example, hair is among the most important materials for brush-making, along with ramie threads for binding the base of the brush, combs for the refinement of hair condition during each process, and high-quality bamboo for the brush handle.
Over a long period of time, Hakuhodo Co., Ltd., and Mejiro Institute of Urushi Research and Restoration have established direct relationships with users and creators through interactive communication. Thanks to this, hope for improved procurement of the needed materials is beginning to appear little by little. Going forward, the Agency for Cultural Affairs and TOBUNKEN will join the relationship and make efforts to expand the network of raw materials producers.
Participants at the opening ceremony
Lecture on basic chemistry using molecular models
Practical session on waste solvents and their disposal
Since FY2021, the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been offering training sessions that provide the scientific information necessary for cultural property restoration. These sessions incorporate insights gained from our research at TOBUNKEN. The program is designed for specialists with restoration experience in cultural properties, museum materials, library materials, and so on, and is intended for professionals with extensive practical field experience.
The fifth iteration of the training was held over three days from September 30 to October 2, 2025, with 16 participants in attendance. The lectures, which included practical sessions, covered the fundamental scientific knowledge considered essential for cultural property restoration. Researchers from TOBUNKEN delivered lectures on the essential chemistry required for cultural property restoration, including adhesion and adhesives, the science of paper and its deterioration, responses to biological issues, and the necessary precautions when using and disposing of laboratory equipment and chemicals.
In response to requests from conservators, we developed a more practical and field-applicable curriculum. Despite the limited time available, participants were highly engaged in proposing scientific approaches to real-world challenges, networking, and sharing information. Post-event surveys revealed positive feedback, with many participants rating the program as “extremely beneficial.” We also received specific requests for scientific insights to be applied in future restoration work. Taking these opinions into account, we plan to continue offering similar training programs on an ongoing basis.
Participants after the opening ceremony
Since FY2019, the Center for Conservation Science of the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has put effort into training programs related to restoration treatments for cultural properties, inviting international specialists and implementing these programs in collaboration with partner institutions. Until last year, the workshops had been co-organized with the National Center for Art Research, Japan (NCAR). This year, the National Museum of Western Art (NMWA) was also added as a partner, making it a three-institution collaborative initiative.
The theme of this year’s program focused on “frames,” which, much like hyōsō (mounting) in East Asian paintings, have long played an essential role in the display and protection of paintings. Despite their close connection with artworks, the importance of frames has yet to gain sufficient recognition in Japan, and information on their conservation practice remains scarce. In light of this situation, Ms. BARROW Yukiko, Senior Conservator at the Victoria and Albert Museum (UK), was invited as the instructor for a three-day workshop titled “History, Technique and Conservation of Picture Frames,” held from October 29 to 31, 2025.
The morning lecture sessions took place in the seminar room of TOBUNKEN, where participants (67 in total) received a wide-ranging introduction, from the history and production techniques of frames to contemporary conservation approaches in the UK. In the afternoon, the venue shifted to the Conservation Studio of NMWA, where 15 selected participants engaged in hands-on training in gilding, toning, cleaning, and other conservation techniques currently practiced in the UK.
On November 1, an associated lecture titled “The History and Conservation of Picture Frames in Britain and Japan” was held. Ms. Barrow spoke on the history of frame conservation and the work of conservators in the UK, while Ms. NAKAE Kana, Curator at the Tokyo Metropolitan Art Museum (MOT), gave a lecture on the history of Western-style frames in Japan. The event was attended by 69 participants.
This workshop, marking the first collaborative effort among the three institutions, offered an integrated opportunity to study both the theoretical and practical aspects of frame history and conservation. The program proved highly fruitful and is expected to contribute to the future advancement of conservation and restoration practices in Japan.
Applying agricultural sheets to prevent weed growth as part of cultivating kōzo.
Mr. Fukunishi explaining about kōzo raw material.
Although a wide range of tools and raw materials are used in the preservation and restoration of cultural property, fine arts, and crafts, many are at risk of being discontinued in the future due to a lack of skilled successors and increasing difficulty in securing the necessary materials. In response to this situation, the Center for Conservation Science, Department of Intangible Cultural Heritage, and the Department of Art Research, Archives and Information Systems at the Tokyo National Research Institute for Cultural Properties (TOBUNKEN) has been involved in the commissioned research of “Investigation of Tools and Materials Used for the Preservation and Restoration of Fine Arts and Crafts” as part of the project of the Agency for Cultural Affairs, “Support for the Management of Tools and Materials Used for the Preservation and Restoration of Fine Arts and Crafts.” This report introduces a field survey of the cultivation of kozo (paper mulberry), the raw material for washi (Japanese paper), which is essential for the restoration of cultural property. It also presents the current use of wood ash in the cooking process used to obtain kozo fibers.
We visited four kozo fields in Yoshino Town and Gojo City, Nara Prefecture, on June 9-10, 2025, and learned about the meticulous work involved in tasks called mekaki (the removal of unnecessary new shoots and buds to concentrate nutrients on the remaining ones) and weed control, as well as the various innovations and challenges involved in the cultivation process. There is no end to the challenges, such as determining the cause of “red streaks” that appear on the inner bark, which reduce the usable amount of raw material because they discolor the fibers, and dealing with insects that were not seen in the past. The number of people responsible for this type of cultivation management is decreasing year by year, which poses a significant challenge in terms of ensuring a stable supply of this raw material.
We also visited the paper-making factories of Mr. FUKUNISHI Masayuki and Mr. UEKUBO Ryoji. The raw materials and wood ash are carefully selected and the delicate process of removing inclusions one-by-one by hand is repeated, because such inclusions make the material unsuitable for the restoration of cultural property. The issue of ensuring a stable supply of wood ash in the future was also discussed. An alkaline solution obtained from wood ash is essential for extracting kozo fibers, but it is also becoming increasingly difficult to procure the ash to obtain good quality fiber.
Going forward, we will conduct scientific research into the interactions between ash derived from various plant species and various raw materials and woods, with the aim of addressing specific challenges. In parallel, we will focus on strengthening our role as a network hub, connecting experts and knowledge across related fields, while continuing our ongoing efforts to document production techniques and processes.
Peeling bark from a tree using a customized spoon
Peeling off the outer parts and extracting the inner parts
Children focusing on washi-making with Mr. Fukunishi
People engaged in noriutsugi supplies intently listened to the explanation by Mr. Fukunishi
“Neri,” a substance extracted from noriutsugi trees, is essential for making Uda washi (Japanese traditional paper) that is used for cultural property restoration. Under the strong sunshine in early summer, people in Shibetsu Town, Hokkaido, carefully remove bark from noriutsugi and peel off its outer parts by hand to extract the inner parts. Furthermore, to reduce reliance on the wild species, they have begun to grow noriutsugi trees in nurseries.
Four members of the Tokyo National Research Institute for Cultural Properties (TOBUNKEN), Mr. NISHIDA Noriyoshi, Head of Analytical Science Section, Center for Conservation Science, Ms. ICHIMIYA Yae, Associate Fellow of the same Center, Ms. MAEHARA Megumi, Head of Intangible Cultural Properties Section, the Department of Intangible Cultural Heritage, and Mr. ODAWARA Naoya, Associate Fellow of the same Department, visited Shibetsu Town from June 24 to 27, 2025. They inspected the process of barking noriutsugi and peeling off its outer parts, and video-recorded the way to grow nursery trees with talks provided by the related parties. They also participated in and video recorded dissemination activities, including a workshop by Mr. FUKUNISHI Masayuki, a holder of selected conservation techniques for handmade washi essential for mounting (Uda washi paper) held at the Shibetsu Town Culture Hall, targeting elementary school students and the wider public. These videos are planned for use in research, education, and dissemination related to the succession of cultural properties after editing.
TOBUNKEN concluded an agreement on collaboration and cooperation on materials for cultural property restoration with Shibetsu Town on November 2, 2023. Recording and disseminating the activities to ensure sustainable supplies of noriutsugi and dissemination activities are expected to benefit this collaboration and cooperation.