The Jiangxue Palace is part of the imperial garden of the Imperial Museum, a world cultural heritage site. In this work, the techniques and components of its color paintings are described and analyzed. The color painting represented a significant architectural component in the Ming and Qing dynasties. This paper analyzes the structure relationship of color painting, morphology, pigment composition, pigment crystal characteristics, and the composition of binder and filler in the plaster by using ultra-depth three-dimensional microscopy, polarized light microscopy, scanning electron microscopy-energy dispersive spectrometry, micro-Raman spectroscopy, X-ray diffraction, Fourier transform infrared spectrometry, and pyrolysis–gas chromatography–mass spectrometry. The Jiangxue Palace paintings are composed of multi-layered structures using pigments such as emerald green, lead white, and lead red (minium). The cross-sections of each structure are composed of a pigment layer (green and white), plaster (albite, anorthite, calcite, tung oil, and flour), and an underlying base of red minium. This research is conducive to a comprehensive understanding of the production technology of the Jiangxue Palace color paintings. The results provide a basis for the subsequent protection and repair of this valuable world cultural heritage site.

The Taidong Tomb in the imperial tombs of the Qing dynasties has great aesthetic value and a rich history. In this study, we conducted the first investigation ever performed on the raw materials used in the paintings in the Taidong Tomb. Energy dispersive X-ray spectroscopy (EDX), polarized light microscopy (PLM), X-ray diffraction (XRD), micro-Raman spectroscopy (m-RS), Fourier-transform infrared spectroscopy (FTIR) and pyrolysis–gas chromatography–mass spectrometry (Py-GC/MS) were used to comprehensively analyze the painting of Long’en Hall, Xipei Hall and the ceiling of Minglou. In the conclusion of the study, the paintings were found to contain natural mineral and synthetic pigments, including atacamite (Cu₂Cl(OH)₃), azurite (2CuCO₃·Cu(OH)₂), vermilion (HgS), carbon black (C), anglesite (PbSO₄), white lead (2PbCO₃·Pb(OH)₂), synthetic emerald green (Cu(CH₃COO)₂·3Cu(AsO₂)₂) and ultramarine ((Na,Ca)₈(AlSiO₄)₆(SO₄,S,Cl)₂). This allows us to conclude that some of the architectural paintings were repainted in the mid-to-late 19th century. The mortar layer may consist of brick ash (albite, gismondine), lime water, tung oil and flour. The fiber layer material may be ramie. Researching the raw materials of the paintings in the Taidong Tomb is of great value because it provides scientific data for the future preservation of the paintings in the tomb.

In recent years, based on the urgent need in the field of cultural heritage conservation, the research and development of coatings have attracted much attention. FEVE (trifluorovinyl chloride and vinyl ether copolymer) is one of the reinforcing materials in the protective coatings of color paint. However, it has problems such as compactness, low tensile strength, and poor resistance to aging. Therefore, modified graphene was introduced and combined with FEVE coatings (FEVE/m-GO) to optimize their adhesion, compactness, resistance to corrosion, and performance at shielding the paintings from ultraviolet light. The structural features of the hybrid films were characterized by UV–Vis spectroscopy, transmission electron microscopy, infrared spectroscopy, etc. In addition, the water absorption, mechanical properties, color difference test, and aging resistance of the FEVE/m-GO and simulated samples were investigated. The results showed that the hybrid film with 0.04% m-GO incorporation as an effective consolidant exhibited outstanding comprehensive performance. This composite material was used in the protection and consolidation of the Sanyou Xuan ancient architectural color painting in the Palace Museum, which opened up a new way of thinking about the long-term conservation of color paintings.

This research sheds light on the analysis of pigments and adhesives applied on a color painting on wooden architecture in Taiping Heavenly Kingdom Prince Dai’s mansion, located in Changzhou, Jiangsu Province in China. Four samples were collected from the painting above the building beam in the mansion, and the samples were analyzed and identified using a series of techniques, including polarized light microscopy (PLM), scanning electron microscope coupled with an energy-dispersive X-ray spectroscopy (SEM-EDS), micro-Raman spectroscopy (m-RS) and Fourier-transform infrared spectroscopy (FTIR). The results indicate that the red, black, blue, and green pigments were identified to be cinnabar, ivory black, indigo, and phthalocyanine green, respectively. The green pigment was inferred to be a lately repainted pigment based on its production age, suggesting that this ancient building had been refurbished or repaired. Given the good stability and visual effect of this green pigment, it is suggested to be used in future conservation processes. The pyrolysis-gas chromatography/mass Spectrometry (Py-Gc/Ms) results indicate that glue containing protein was used as a binder for the pigment samples, and that walnut oil might have been applied to the wooden architecture as a primer before painting. Our findings can well inform curators and conservators of the selection of appropriate restoration materials if necessary, and also provide data support for conservation of similar ancient buildings in southern China.

This paper analyses the decorative polychrome painting of architectural members (caihua) that has survived in the Hall of Mental Cultivation (Yangxindian) in the Forbidden City, Beijing. Beginning with the Yongzheng emperor, the Hall of Mental Cultivation was the residence and centre of daily governance for Chinese emperors. Combining information gained through on-site surveys and scaled drawings executed during a recent conservation project with evidence from historical records and other sources, this study finds that the remaining decorative polychrome painting can be dated to four different historical phases: the reign of the Jiajing emperor; the late Ming and early Qing dynasties; the reign of the Qianlong emperor; and the late Qing Dynasty and beginning of the Republic of China. It reveals that the designs of decorative polychrome painting on architectural members are closely related to changes in the functions of the buildings and imperial use. As part of an investigative conservation project, the study aims to provide a reliable basis for the conservation and repair work in the next step.