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


Seven years have passed since the 2011 Tōhoku earthquake and tsunami.

Scene of the private view
Scene of the exhibition

 It is seven years since the 2011 Tōhoku earthquake and tsunami. We offer our sincere condolences on the death of victims of the unprecedented tragedy, and we express our gratitude to those who have worked in restoration assistance following the disaster. Iwate Prefectural Museum, where thousands of cultural assets that were damaged by tsunami have been treated for stabilization treatment, held panoptic exhibitions from March to May, which demonstrated to us the importance of conservation of tsunami-damaged assets. During these exhibitions, we exchanged information with specialists involved in stabilization work of damaged assets.
 Two exhibitions, “Asu ni tsunagu Kesen no takaramono–Tsunami de hisai shita Rikuzentakata shiryo wo chushin ni (The treasures of Kesen that we pass on to the future generations –with a focus on tsunami-damaged assets in Rikuzentakata)” (March 3rd to 28th, 2018) and “Mirai heno yakusoku–ima katari hajimeta Kesen no takaramono” (A promise to the future–the treasures of Kesen that start to talk now)” (April 3rd to May 6th, 2018), introduced the damaged cultural assets that stabilization treatment of which was finished. During the opening ceremony, the deputy director general of our institution, Eriko Yamanashi, gave a congratulatory speech by guests, instead of the director general, Nobuo Kamei, who could not come to the museum. In the private view, the director of Center for Conservation Science, Chie Sano, gave an explanation of our study on the stabilization processing of tsunami-damaged documents. It seemed that the exhibitions were strongly motivated activities. There were descriptions of every asset’s condition before stabilization, and stabilization methods used, as well as the cultural assets that stabilization treatment of which was finished.
 Through seven years of the work, stabilization treatment of 220,000 items, out of 460,000 damaged items, has been completed. However, 240,000 cultural assets are still awaiting stabilization in the museum. The number of tsunami-damaged assets is enormous. In addition, the assets have many types of problems such as unpleasant odor. We would like to contribute to the conservation of damaged cultural assets through scientific study.


Restoration of the Kawasaki Ki-61 Hien, Possessed by the Japan Aeronautic Association

Complete view of the Hien. The national marking (red sun) on the surface of the right-hand main wing is reproduced with projected red light.
The national marking (red sun) on the right-hand side of the fuselage is reproduced every two minutes by projection mapping.
Visible are two traces of the national markings (red sun) on the left-hand side of the fuselage. The larger one is a trace of one painted after the war.
The trace of the airframe number “6117” below the supercharger air intake.

 The Kawasaki Ki-61-II Hien (flying swallow), possessed by the Japan Aeronautic Association, was manufactured at the Gifu Works of Kawasaki Aircraft Co., Ltd. in 1944. When World War II ended in 1945, it belonged to the Air Evaluation Department of the Imperial Japanese Army located at the Fussa Air Base in Tokyo. Although almost all Japanese aircraft were scrapped after the war, this fighter was not disposed of for some unknown reason and had been displayed at the US Yokota Air Base until 1953. This Hien is now the world’s only airframe displayed in a museum. (There have been several attempts to restore the Hien, using the wreckage retrieved from New Guinea.) This fighter was transferred to The Japan Aeronautic Association from the US forces for free in 1953. Until 1986, when it was exhibited in the Chiran Peace Museum (Minamikyushu City), the fighter was displayed all over Japan. Meanwhile, some of its parts were lost and the airframe was damaged. When necessary, temporary repairs were carried out while painting and marking distinctly different from the original ones were applied from 1965 onwards.
 In recent years, the Japan Aeronautic Association has begun to recognize anew the Hien as a cultural property through joint research with the Center for Conservation Science. Kawasaki Heavy Industries, Ltd. (hereinafter KHI) offered full cooperation in restoration of the Hien as a commemorative project to celebrate the 120th anniversary of its foundation in 2016. In 2015, the fighter was restored at its Gifu Works for almost a year.
 Prior to its restoration, it was decided that the Hien would be restored as a cultural property through negotiation between the Japan Aeronautic Association and KHI. As for individual items for restoration, KHI proposed restoration methods, which the Association checked and accepted. The restoration by KHI covered a wide range of issues, including the removal of the paint applied on the airframe surface, removal of non-original parts added after the war, and production of new replica parts such as the nose panel above the engine and the instrument panels of the cockpit.
Removal of the paint on the airframe surface revealed the traces of the drilling tool blade that slid over the skin of the wings during manufacture, as well as traces of national markings and caution notes on various parts of the airframe. It also revealed the fact that the airframe number (construction number) was “6117.” Repainting of the national markings, which was proposed by KHI, was not implemented due to a possibility that new paint might affect the airframe surface and for the value of exhibiting the discovered traces as they are. When the Hien was exhibited at Kobe Port Terminal Hall (Kobe City) for about one month in autumn 2016, the national markings were reproduced with wrapping film at the request of KHI. The film was peeled off after being delivered to the Kakamigahara Aerospace Science Museum (Kakamigahara City). Although the museum had been closed since September 2016 for renovation, the disassembled Hien was displayed in the repository from November 2016 through November 2017.
 After the restoration by KHI, the Japan Aeronautic Association surveyed the Hien under the supervision of the Center. This led to the removal of deteriorated rubber parts and the replacement of the fabric on the control surfaces (the rudder, the elevators, and the ailerons). Like many other aircraft of that time, the control surfaces are composed of a metal framework covered with fabric. When the fabric was replaced in 1986, it was not sewed to ribs, which resulted in creating a different appearance. Therefore, the Center researched the material of the fabric used in the WW2 era so as to provide supporting data for replacement of the fabric. This replacement was carried out from autumn 2017 through February 2018. The Center also took photos of the airframe before and after the reassembly for the record.
 When the Museum was reopened after the renewal as “Gifu-Kakamigahara Air and Space Museum” on March 24th, 2018, the Hien became one of the main exhibits there. According to the Museum, many visitors positively accept the unpainted national markings, and this fact indicates that the perception of aircraft as cultural property is spreading in our society.


Public Exhibition of the Conservation Facility for Mural Paintings of Takamatsuzuka Tumulus, a National Treasure

Registration booth for the public exhibition of the conservation facility for mural paintings of Takamatsuzuka Tumulus, a national treasure

 I participated as a staff explained in the public exhibition of the conservation facility for the mural paintings of Takamatsuzuka Tumulus, which are designated as a national treasure. After the dismantling of the stone chamber from Takamatsuzuka Tumulus in 2007, the conservation facility was opened to the public twice a year. From 2017 onward, the frequency of public exhibitions of the facility, along with the mural paintings of Kitora Tumulus at Shijin no Yakata, the Kitora Tumulus Mural Experiential Museum, was increased to four times a year. Tokyo National Research Institute for Cultural Properties has been hosting these events since the first time the facility was opened to the public.
 At the 20th public exhibition held recently, we placed the West Wall (Group of Female Figures, White Tiger, and Group of Male Figures) and the North Wall (Black Tortoise) in the area close to the exhibition corridor to provide visitors a view of the progress of the conservation of the mural paintings since they were taken out from the tumulus ten years ago; moreover, visitors can compare the paintings with the mural painting of Black Tortoise from Kitora Tumulus, which was also on exhibition at the same time. Although the event was held during winter, when the number of tourists to Asuka Village is low, it attracted approximately 1,000 visitors, including people without pre-registration. Many visitors were amazed with the progress of the cleaning of the mural paintings, and left with newly developed interests in the future restoration process and exhibitions.


Opinion Exchange with Bagan Lacquerware Technology College and Visits to Lacquerware Production Sites in Myanmar

Visit to a lacquerware production site in Myanmar

 The Tokyo National Research Institute for Cultural Properties conserves and restores cultural properties, as well as conducts research and study in collaboration with educational/research institutes, private and other organizations, not only at home but also abroad. As one of these activities, the Institute reached an agreement on the protection of lacquer work cultural heritage in Myanmar with the Small-Scale Industries Department of the Ministry of Co-operatives, Myanmar in 2014 while organizing a workshop on lacquerware at Bagan Lacquerware Technology College in 2016. Even after the expiration of the agreement, another workshop was held at the College in February 2017, where lacquerware was practically observed and lectures on conservation/restoration cases and scientific analyses were given, maintaining the cooperative relationship.
 On December 7th, 2017, we visited the College to decide on the policies for future cooperative programs by exchanging opinions. Its main topics were the safety and features of lacquerware sold in the Bagan area from a scientific perspective, and both parties agreed that mutual understanding should be promoted further. In addition, we visited lacquerware production sites in Myanmar for future cooperation on December 7yh and 8th, promoting a better understanding of Myanmar’s lacquerware.


Survey of jet-engine parts in the possession of International Christian University

Two exhaust nozzles of a jet engine carried into the laboratory. The right part has a cover
Process of separating the cover

 The Center for Conservation Science, under the request of International Christian University, together with Japan Aeronautic Association, conducted survey of two materials which were excavated on the university campus in 1950 and were most likely to be parts of a jet engine. A survey conducted at the university on May 20th, 2017 revealed that they were likely to be exhaust nozzles of a jet engine manufactured in Japan during World War II. In response to this result, a more detailed investigation was conducted at the Center’s laboratory from July 6th to October 26th.
 In addition to survey of the literature and visual inspection, measurement of major dimensions and weight and survey of the structure material were carried out, together with photographic recording. Furthermore, X-ray CT photography was conducted with the cooperation of the Tokyo National Museum for the purpose of investigating the composition of the material and the internal structure. One of the two surveyed materials consisted of two parts. After being carried into the Center, it was carefully separated, foreign matters such as dust and dead leaves adhering to the surface were removed, and anticorrosive treatment was provided.
 Through the investigation, it has been confirmed that there are engravings similar to those engraved on other Japanese aircrafts manufactured during the wartime, all parts are made of stainless steel and therefore heat resistant, and the shape and structure are similar to the exhaust nozzles of jet engines “ネ130” and “ネ330,” which were also developed in Japan during the wartime. As a result, it is concluded that the materials are highly likely to be exhaust nozzles of a jet engine made in Japan and that the corresponding engine is “ネ230,” developed together with Hitachi by Nakajima Aircraft Company, which existed during World War II on the grounds of International Christian University. The exhaust nozzles are considered to have been never used because of the absence of any traces that they were attached to the body of a jet engine using bolts.
 Out of the jet engines developed in Japan during the wartime, only two examples of parts have been confirmed to exist. Therefore, the materials surveyed this time are quite valuable, showing both the advancement of Japanese technology in the 1940s and the process of the aircraft development in Japan.
 On October 26th, the representatives of the survey team visited International Christian University and submitted an interim report to President Junko Hibiya. In the future, the final report will be compiled including results of the survey on the value as cultural property.


Interview for building Cultural Heritage Disaster Risk Mitigation Networks

Fig.1 An interview on site
Fig.2 The freeze-drying equipment for tsunami-damaged documents

 Natural disasters, such as earthquakes and typhoons, are causing serious damage to cultural property. The National Institute for Cultural Heritage has conducted interviews with museums and prefectural offices regarding the risk management of cultural property all over Japan in order to build networks providing for disasters, because it is necessary to protect our cultural heritage and pass it on to future generations. We are in charge of Hokkaido and Tohoku areas, and conducted an interview with Tohoku University of Art and Design on September 15.
 In the university, documents that were damaged by the Great East Japan Earthquake have been subjected to a freeze-drying process in order to dry them. We obtained information giving a detailed description of the time of the disaster in 2011. In addition, we learned about some problems and tasks on site.
 Through these interviews, we found that there were many types of risk management for cultural property in each region. We will continue to conduct interviews, and aim to build Cultural Heritage Disaster Risk Mitigation Networks that help people and protect our cultural property when problems arise.


Seminar for Museum and Gallery Curators in Charge of Conservation

Practical training

 This seminar has been conducted since 1984 in order to convey basic knowledge and techniques to curators working on the conservation of materials at the cultural property conservation facilities. For 2017, the two-week seminar starting from July 10 attracted 31 participants throughout Japan.
 The curriculum of this seminar consists of two major topics: management of the facility environment such as temperature and humidity, air quality, and prevention of pest damages; factors and manners of deterioration according to material types, as well as its prevention. Experts inside and outside the Institute gave lectures and practical training. For the “Case Study,” where the participants experienced the museum environment research on site, they visited Saitama Prefectural Museum of History and Folklore. After dividing into eight groups, they implemented research under the theme set by each group, and presented the outcomes at a later date.
 Under the current circumstances whereby many facilities are planning large-scale renovation and major movements related to the conservation of materials, such as shifting to LED lighting, are under way, we will scrutinize the curriculum further for smooth technical transfer of proper management.


Field survey on the conservation and restoration of iron structures in Taiwan

Meeting in the Bureau of Cultural Heritage, Ministry of Culture

 On August 19th (Saturday) to August 27th (Sunday), the Modern Cultural Properties Section of the Center for Conservation Science conducted a survey on the conservation and restoration situation of iron structures built in the Japan colonial period (1895-1945) existing in Taiwan. In this survey, we focused on a large-scale factory and iron bridges.
 The preservation of Japanese colonial buildings began in earnest following the end of martial law in 1987, and about half of all Designated or Registered Cultural Properties are Japanese colonial-era buildings.
 For this survey, although we focused on a sugar-refining plant, since tobacco and brewed liquor factories had a monopoly on the country until the 1990s, many of their factories and machinery have been left untouched. Although these factories are greatly influenced by their location, many factories in large cities such as Taipei have been assigned new roles by town planners, and are used as commercial and cultural facilities.
 On the 22nd, we visited the Bureau of Cultural Heritage, Ministry of Culture, and held a discussion with Director-general Gwo-Long Shy on the efforts to preserve Taiwan’s cultural assets.
 Since 2000, Taiwan has made efforts to preserve its industrial system of production, distribution and manufacturing. This has led to an active exchange of ideas regarding renewed interest in the preservation of Japan’s own industrial heritage.


Workshop on Conservation Science for Conservators of Japanese Painting and Calligraphic Works

Lecture by Ms. Sano on the safe handling of organic solvents
Workshop by Mr. Kimishima on how to remove stains

 To conserve Japanese paintings, calligraphic works and other pictorial artifacts, we are now increasingly required to have some knowledge of conservation science. To meet these demands of conservators who wish to learn how to handle chemicals, particularly those that have recently become more popular in restoration sites, and how to apply them in conservation and restoration works, the Tokyo National Research Institute for Cultural Properties and the Association for Conservation of National Treasures (ACNT) jointly conducted a workshop with training program for conservators from August 8 to 9, 2017, which included lectures on basic knowledge and practical work sessions. The workshop aimed to provide hands-on knowledge that can be applied to actual conservation works. To achieve this purpose, we designed a curriculum that would help participants accurately understand the chemical property of organic solvents and enzymes as well as the proper handling of basic laboratory instruments and chemicals for more effective and safer restorations.
 A total of 11 people, one from each corporate member of ACNT, participated in the workshop. Dr. Sano, Director of the Center for Conservation Science; Dr. Sato, Head of the Biological Science Section; and I provided lectures on the safe handling of organic solvents; integrated pest management (IPM) for cultural properties at restoration studios; and removal methods of adhesives and stains, respectively. Based on these lectures, the participants practiced removing various types of stains on the sheets of paper that we prepared, by using suitable solvents and enzymes. The practical work session also covered other topics such as the use of cyclododecane as a temporary protective coating for water-sensitive colorants. Mr. Kimishima, ACNT’s Senior Conservator, taught in the work session and provided hands-on training to the participants.
 The program ended with a lively Q&A session and discussion. We will continue to hold such workshop in the future.


Field study of treatment conditions for tsunami-damaged objects

Rikuzentakata City Museum (formerly Oide Elementary School)
Inspecting the water quality in tubs used for desalination of paper documents

 Many thousands of cultural properties were severely damaged by the tsunami that occurred following the 2011 Off the Pacific Coast of Tohoku Earthquake. Although six years have passed from the disaster, treatment of the tsunami-damaged cultural properties continues in the disaster-stricken areas. In order to investigate the occurrence of volatile organic compounds, which are harmful to workers’ health, we made a contract with Rikuzentakata City and conducted a survey on the treatment methods for the tsunami-damaged cultural properties and on the working environment in the facility where treatments are conducted.
 We visited the treatment facility in the Rikuzentakata City Museum, which is located in a temporarily closed school facility in Iwate Prefecture, for on-site research in August from the 25th to 26th. Damaged folk cultural properties are bathed in water for desalination in the school yard. On the first floor, paper documents are treated for desalination in a teachers’ room and cleaned natural history specimens are classified in a classroom. Treated objects are stored separately according to each type of cultural property in the classrooms on the second floor or a temporary installed storage facility in the gymnasium.
 We were able to obtain a lot of valuable data about the air quality in the facility and water quality during treatment, helped by the cooperation of the museum staff. Temperature and humidity in the facility are continuously measured even now. By the end of this fiscal year, we plan to propose improvements after collecting data.


Optical Study of the Ryukyu Paintings

On-going optical study of the Ryukyu paintings at Okinawa Prefectural Museum & Art Museum

 We conducted an optical study of the Ryukyu paintings at Okinawa Prefectural Museum & Art Museum on June 20-23, 2017. In order to investigate the depiction techniques and coloring materials, high-resolution color imaging and X-ray fluorescence spectrometry were applied for ten paintings held by the Okinawa Prefectural Museums and the Okinawa Churashima Foundation. Ryukyu-koku no zu, an important cultural property, held in Okinawa Prefectural Library was also investigated.
 Many of the Ryukyu paintings have disappeared due to the warfare of World War II, and sufficient research has not been performed. We have conducted optical studies of the Ryukyu paintings located inside and outside Okinawa Prefecture since 2008. Optical study of the Ryukyu paintings will continue to be conducted in the future and the results will be published. We believe that the study is of great help in deepening the understanding of the Ryukyu paintings.


Visit to Earthquake Remains Conserved in Taiwan

Damaged Guangfu Junior High School exhibited in the 921 Earthquake Museum of Taiwan
Projection mapping focused on the fault exposure in the Chelungpu Fault Preservation Park

 A fault exposed in a paddy field due to the 2016 Kumamoto Earthquakes attracted much attention, calling for the necessity of its preservation (as a result, it is designated as a natural monument by Mashiki Town today). As a good example of disclosing and utilizing such preserved fault exposure, the Nojima Fault Preservation Museum (where the fault exposed due to the Hyogoken-Nanbu Earthquake, which triggered the Great Hanshin-Awaji Earthquake, is preserved) established in 1998 is well-known in Japan. In 1999, the Jiji Earthquake occurred in Taiwan. We visited a museum constructed following the Nojima Fault Preservation Museum with further development near Taichung, the damage of which was specifically serious. The 921 Earthquake Museum of Taiwan works well as a disaster prevention museum, which shows earthquakes with a focus on the effectiveness of quake resistance and quake-freeness by conserving a damaged junior high school building with a shelter constructed as the exterior walls of the museum for disclosure. On the other hand, the Chelungpu Fault Preservation Park is a scientific museum, where an exposed fault section confirmed during the survey is directly exhibited inside the housing. The museum also shows the mechanism of an earthquake and the history of past quakes. Particularly, by means of project mapping focusing on the fault surface, they visually show the history of complicated strata in sequence, which is difficult to understand from the current plane of stratification. Application of such an approach is expected in various fields also in Japan, including explanations about remains at archeological sites besides the exhibition of the strata.


Research on the great Torii of Itsukushima Shrine after restoration

Research on the great Torii of Itsukushima Shrine

 The Center for Conservation Science has studied restoration materials for cultural properties.
 The great Torii of Itsukushima Shrine is located on the coast. Since it is exposed to the wind, the rain and the waves, we have to select restoration materials with high weathering performance, which can also save restoration time.
 Based on the above, we studied which fillers and surface-finishing agents were the most suitable for use in the great Torii from 2010 to 2016. After a small pillar of the great Torii was partially restored last year, we researched it on May 25.
 We are going to observe the progress and cooperate with conservators for restoration planning.


Investigation of the Causes of Odors from Paper Materials Damaged by the Tsunami

Installed equipment

 We have been conducting a joint project with the Iwate Prefectural Museum to determine the methods to stabilize the paper materials damaged by the tsunami in the City of Rikuzentakata, Iwate. In Iwate Prefecture, many documents and other paper materials were damaged by the tsunami that hit the area in 2011. We have already stabilized approximately 90,000 paper materials, but it is still unclear when we will be able to complete the work of stabilizing all the damaged materials. The joint study conducted up to last fiscal year has enabled us to estimate almost all causes of the odors emitted from the paper materials. In this fiscal year, therefore, we have been working on establishing the methods to eliminate the odors from the stabilized materials, and also on a plan to keep records of the stabilization processes to determine how to improve them and what conditions cause paper materials to develop odors. On May 17, we visited the Iwate Prefectural Museum to discuss plans for this fiscal year as well as to install some equipment, together with our co-investigator, Mr. Hideo AKANUMA, in the conservation and restoration laboratory for tsunami-damaged cultural properties of the Rikuzentakata City Museum, which is located next to the Iwate Prefectural Museum. In this laboratory, we tentatively installed the equipment to monitor water temperature and oxygen concentration levels, and also installed surface temperature/humidity measuring equipment to check the temperature and humidity of the laboratory as well as to identify the transfer of temperature inside it. We plan to conduct joint investigations in June and July, each for a period of approximately one week.

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A workshop on insect damage to wooden cultural properties organized in Isfahan, Iran

A scene from the workshop
A field survey on the damage situation of a historic building

 Structures of historical buildings in Iran are mainly made of bricks or clay walls. However, wood is also used for making its roof frame, beams, window frames and so on. Damage of termites is found extensively in the central to southeastern parts of Iran, including Isfahan according to a preliminary survey conducted last fiscal year, and it is the major issue of the conservation of historical buildings in these regions. Termites are notorious as an insect pest for wooden materials. Their damage used to be widely found in Japan as well, but preventive measures have been gradually established to date. In order to support for establishing appropriate measures for conserving wooden built heritage and historical objects in Iran by sharing such knowledge, Tokyo National Research Institute for Cultural Properties (TNRICP) and Iranian Cultural Heritage, Handicrafts and Tourism Organization (ICHHTO) co-organized a workshop on insect damage to wooden cultural properties in Isfahan from April 17th through 19th, 2017.
 From Japan, Mr. Masahiko TOMODA and Mr. Hiroki YAMADA of the Japan Center for International Cooperation in Conservation of TNRICP, Mr. Yukio KOMINE of the Center for Conservation Science of TNRICP and Mr. Kazushi KAWAGOE, Senior Researcher of Institute for Environmental Culture, participated in the workshop. From Iran, more than 20 experts got together from various parts of the nation, including Yazd, Tehran and Gilan, as well as Isfahan. On Day 1 and Day 3, presentations were given from both sides on materials and structures of historical buildings in both countries, and actual cases and monitoring surveys of insect pest damage to them. On Day 2, to discuss specific measures and others, all participants visited historical buildings to conduct a survey to identify termite damage and a test to install IGRs (Insect Growth Regulators) that does not affect the environment badly.
 We heard that after the workshop, ICHHTO began preparation for establishing a new laboratory engaged in research on the prevention of termites in Isfahan. We believe that this workshop was able to contribute to conserving Iran’s valuable cultural heritage in any way.


Publication of 『Report of the Optical Study for the Ryukyu Paintings 』

『Report of the Optical Study for the Ryukyu Paintings』

 The 『Report of the Optical Study for the Ryukyu Paintings』was published by the Tokyo National Research Institute for Cultural Properties in March 2017. The Ryukyu paintings refer to paintings drawn in the Ryukyu islands during the Ryukyu dynasty era, although they have not been definitively defined. The paintings were largely influenced by Chinese and Japanese paintings, but the depiction and coloring are different from those paintings. Many of the Ryukyu paintings disappeared during World War II, and sufficient research has not been performed.
 We have conducted an optical study of the Ryukyu paintings located inside and outside Okinawa Prefecture since 2008. In this report, high-resolution color images and the results of coloring materials by X-ray fluorescence spectrometry were analyzed for eleven paintings held by the Okinawa Prefectural Museums and the Okinawa Churashima Foundation.. It is the first time that an optical study of Ryukyu paintings has been conducted, and we believe that publishing the results of the study is of great help in deepening the understanding of the Ryukyu paintings. We hope that this report will be widely used for research on the painting and art history of Japan. Although this report is not for sale, it can be viewed at prefectural libraries throughout the country.


After Returning the Gold Picture Screens

How the screens are being loaded

 In the wake of a gas fumigation incident due to an erroneous agent in 2010, five gold picture screens became discolored. Based on the method that was determined as a result of discussing a policy for addressing the issue among parties concerned, including the Tokyo National Research Institute for Cultural Properties (TNRICP), these gold picture screens’ surface had been stabilized since 2012. They were finally returned to the Ekingura (Konan City, Kochi Prefecture) on April 17th, 2017 (carried out of the TNRICP on April 14th). With the screens’ safety as top priority, as a treatment to stabilize the surface, the following measures were taken: 1) The screens were dismantled to perform cleaning to remove the agent on the paper; 2) Prevention of the exfoliation of a paint layer, repairing of the paper, mending of a rupture of the paper, replacement of the lining paper and retouching of the repaired places; and 3) replacements of the foundation, osoigi frame support, karakami lining paper and metallic materials and reconstruction into a 2-panel folding screen. Each screen was packaged in order of a gas barrier bag, a screen bag and a cardboard box and delivered by a land vehicle specifically designed to transport art objects.
 In the presence of the Kumamoto Art and Culture Promotion Foundation, to which they were returned, the five screens were stored in a treasure house safely and the Ekingura Management Committee, the Akaoka Gold Picture Screen Preservation Association and those parties concerned in Kochi Prefecture and Konan City appeared to be pleased. Though it was unfortunately rainy, when the truck arrived and the screens were carried in, it stopped raining as if the parties’ wishes came true. The TNRICP will give advice on a preservation environment for the gold picture screens from this point onward.

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Basic Research Underway for Developing New Ways of Killing Insect Pests in Historical Wooden Architecture (How to Capture Insect Pests)

A FIT
installation of FIT

 The Center for Conservation Science has been moving forward the basic research on “hot-air processing” as one of the new ways of exterminating insect pests in historical wooden architecture. It heats a structure while maintaining a steady moisture content so that wood or coloration sustains no damage, thereby exterminating insect pests that perforate members inside the building, such as columns and beams, or cause feeding damage to them.
 In research such as this, it is ideal to use insect pests that actually cause damage when evaluating insecticidal effects. However, it becomes necessary to identify ways of collecting living insect pests efficiently or to establish an artificial rearing method to ensure their steady availability. To that end, we here discuss ways of capturing them.
 In the case of ordinary sticky traps for capturing flying insects, because an adhesive substance adheres to the insect pests captured, it is difficult to catch them alive. We therefore looked into how they are captured by applying a method called a Flight Interception Trap (FIT). The FIT utilizes the characteristic that a flying insect shrinks its wings or legs and falls when hitting an obstacle and thus is made up of a transparent collision plate and a trapping container installed underneath.
 When we conducted a survey on insect pests captured by using a FIT at a temple on Mt. Nikko this fiscal year, we succeeded in capturing the intended insect pests (mainly deathwatch beetles) alive. Being able to capture them alive can not only provide clues to elucidating their biology or life history but also lead to artificial rearing.
 We believe that it is important to accumulate the results of such basic research activities as the foundation underpinning the development of new ways to exterminate insect pests in historical wooden architecture.


Investigation of inner structure of Baird’s beaked whale specimen

Damaged Baird’s beaked whale specimen being X-rayed for investigation

 The Baird’s beaked whale specimen (Berardius bairdii : nickname “Tsutchy”) exhibited at the Rikuzentakata Sea and Shell Museum is a whale (total length is about 10m) that was stuffed to celebrate the meeting of the International Whaling Commission in Tokyo in 1954. The specimen was damaged by the great east Japan earthquake and tsunami on March 11th, 2011. After the primary inspection of damage at the museum on May 28th, 2011, the specimen was transferred to the Tsukuba Research Department of the National Museum of Nature and Science on June 30th, 2011. Currently, the project for restoration of the specimen is in progress.
 In this project, it is important to understand the structure of the timberworks and the location of corroded nails inside the specimen. At the request of the National Museum of Nature and Science, Masahide INUZUKA and Midori HAMADA investigated the inner structure of the specimen using X-ray radiography from October 16th to 18th and from 23rd to 25th, 2016. For this research, we used the developing equipment, which is dedicated to imaging plates that were introduced to our institute in 2015. Accordingly, we proceeded with the research by confirming the X-ray transmission images each time they were obtained.
 To investigate the overall inner structure of the specimen with the total length of about 10m, we obtained 375 X-ray images in total. The information about the structure of the timberworks and the location of corroded nails inside the specimen obtained from these X-ray images will be referred to during the investigation using an endoscope and the restoration works.


Completion of the restoration works for the mural paintings in the Kitora tumulus

Packing for transportation

 The Tokyo National Research Institute for Cultural Properties (Tobunken) has been conducting the project “Work on the investigation of the preservation measures for Kitora Tumulus, a special historic site” since 2004. As the mural paintings in the tumulus required conservation treatments, it was decided that they would be removed from the tumulus and currently conserved externally. Three types of conservation treatments were conducted: maintaining the mural paintings in the tumulus, removing the mural paintings from the tumulus stone, and reconstructing the mural painting fragments. The removal of the mural paintings had been conducted for over 6 years, and the paintings were separated into 1143 fragments. The paintings have been reconstructed in the restoration facility in Asuka-mura, Nara prefecture. The Tobunken team has developed conservation techniques and performed experimental checks for this project, and the Association for the Conservation of National Treasures, an association of conservators for Japanese paintings, has applied the developed techniques.
 On August 24th and 25th, 2016, three reconstructed mural paintings, the south wall with suzaku, west wall with byakko, and the ceiling with an astronomical chart were moved from the restoration facility to “Shijin no yakata”. This museum opened on September 24th, and the three mural paintings was exhibited for a month.


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