Yoshihiko Yamashita's research while affiliated with National Research Institute for Child Health and Development, Tokyo and other places

Publications (6)

Article
The purpose of this paper is to present a versatile clamping system to apply controlled pressure during the consolidation of objects or when adhering parts into position. Known as shimbari in Japan, this technique uses flexible fiberglass or bamboo sticks braced against a frame to provide clamping pressure. This paper describes readily available eq...
Article
The purpose of this paper is to present a versatile clamping system to apply controlled pressure during the consolidation of objects or when adhering parts into position. Known as shimbari in Japan, this technique uses flexible fiberglass or bamboo sticks braced against a frame to provide clamping pressure. This paper describes readily available eq...
Article
Full-text available
A comprehensive overview of lead alloys, their deterioration and the range of methods used for conservation of corroded artefacts was invstigated. The study focused on adapting electrolytic reduction, with the aim of preserving as much original material as possible. It investigated the use of conductive polymers in place of simpler electrolyte solu...
Conference Paper
This paper describes the conservation of lifting shell decoration on the Mazarin Chest. The relative Bloom, shrinkage, tack, gloss and colour of 16 Japanese and European collagen adhesives were qualitatively ranked. The working properties and appearance of a range of natural and synthetic materials were compared using facsimile shell on lacquer boa...
Conference Paper
Full-text available
The Mazarin chest is one of the finest pieces of Japanese export lacquer (urushi) to have survived from the first half of the seventeenth century. Much of the value of this piece lies in the decoration, which is finely executed using a wide range of techniques. To date, the conservation of Japanese lacquer has been characterized by distinctly diffe...

Citations

... Areas of delaminating lacquer surface were consolidated with 5-10% w/v Paraloid ® B-72 in xylene, with pressure applied to the surface using the shimbari method ( Fig. 6) (Bainbridge et al., 2015). Xylene was selected as the solvent used for consolidation as it is an efficient solvent for Paraloid ® B-72 and is less likely to swell or blanch the lacquer surface (McSharry et al., 2011). ...
... This causes the formation of pinholes, by decomposition and volatilization of the polymerized urushi (Kenjo, 1988), which initiate microcracking of the surface and associated loss of gloss (Vogl, 2000;Elmahdy et al., 2011;Liu et al., 2011;Thei, 2011). As damage proceeds, microcracks propagate both vertically and horizontally leading to incremental loss of the surface and associated decoration such as makie particles and nashiji flakes (Yamashita & Rivers, 2011a). Progressive photodegradation is also associated with increasing sensitivity to solvents and fluctuations in RH (Ogawa et al., 1998;Obataya et al., 1999Obataya et al., , 2002McSharry et al., 2007McSharry et al., , 2011. ...
... Even a minimal urushi-gatame treatment significantly improves the resistance of a lacquer surface to damage from water and organic solvents (Yamashita and Rivers 2008) and gives a greater range of options for subsequent cleaning and consolidation. ...
... It was necessary to stabilize the metal foil decoration before urushi-gatame otherwise it would have been damaged or dislodged (Rivers and Yamashita 2006). However, even after the loose areas had been consolidated, gaps remained between the back of the foil and the urushi surface below. ...
... In 2013, an agarose rigid gel was successfully exploited on Japanese lacquer objects, to face the complex combination of metals present, namely tin, lead, and iron. The use of a hydrogel system addressed the electrolytic reduction treatment exclusively on the corroded areas, without affecting and altering the surrounding water-sensitive lacquers [69]. Recently agar formulations resulted to be efficient carriers for the electrochemical cleaning of silver threads and silver leaves [70,71]. ...