To delay acidification and deterioration during natural aging, deacidification and reinforcement of paper manuscripts have been the most important technologies to prolong the life of objects. Herein, a novel approach for the conservation of paper manuscripts is proposed using chitosan nanoparticles as Lewis base that leads to both deacidification and strengthening of paper in one-step. Chitosan nanoparticles were prepared through physical ball grinding method and characterized via scanning electron microscopy (SEM), X-ray diffraction (XRD), laser particle size analyzer (LPSA), Fourier transform infrared spectroscopy (FTIR), and atomic force microscope (AFM). To evaluate the resistance of chitosan nanoparticle coating, the mechanical properties of paper after artificial aging were evaluated using dry heat and hygrothermal accelerated aging methods. The SEM, EDX, and X-ray Photoelectron Spectroscopy (XPS) were used to analyze the interaction mechanism between chitosan and Shuxuan paper. The results show that the coated paper had superior durability with respect to pH, tensile strength, and folding endurance. There was a presence of protonated amines in the form of ammonium salts due to ionic bindings with free H⁺ in the acidified paper, and the remaining –NH₂ could be used as a base reserve. Finally, the resulting coated papers displayed good antibacterial properties.

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.

Paper cultural relics such as double-sided printed newspapers and periodicals represent modern cultural heritage. Severe damage such as embrittlement, decay, and dreg generally occur to paper; hence, it urgently needs conservation and restoration. Therefore, herein, a new reinforcement method for the fragile double-sided printed paper cultural relics is proposed with cotton mesh and adhesive PVA217 as reinforcement materials. Using a computer measured and controlled folding endurance tester, a pendulum tensile strength tester, pH meter, pulp viscosimeter, and other instruments, the physical properties of newspaper samples before and after aging were evaluated. In addition, the mechanical properties, chromatic aberration and surface morphology of simulated samples before and after the cotton mesh reinforcement and Japanese washi paper reinforcement were assessed. The experimental results indicate that this new reinforcement method could effectively improve the physical strength, chromatic aberration and durability of the simulated samples. Widespread applications of this cotton mesh reinforcement method for the reinforcement and protection of the red revolutionary cultural relics such as double-sided printed newspaper and periodicals during the Republic of China era are foreseeable.

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.

Paper acidification causes paper relics to undergo embrittlement and decay, to form dregs, and even to break upon a single touch; therefore, reinforcement and deacidification treatments are essential steps for paper conservation and to retard the deterioration and prolong the life of objects. Polymeric adhesives play an essential role in reinforcement and deacidification treatments, although it is not well studied. In this work, the effect of polymeric adhesives on the conservation process and their protective effects on acidified paper relics were studied. Firstly, three polymeric adhesives, including wheat starch paste, polyvinyl butyral (PVB), and polyvinyl alcohol (PVA), were selected as research objects. Subsequently, their effects on four popular conservation methods were further discussed, including traditional mounting, hot-melt with silk net, alcohol-soluble cotton mesh, and water-soluble cotton mesh. Additionally, as an example, the reversibility and long-term durability of water-soluble adhesive PVA-217 were assessed. Using a computer measured and controlled folding endurance tester, pendulum tensile strength tester, tear tester, burst tester, FT-IR, video optical contact angle tester, and other instruments, the conservation application of water-soluble adhesives in paper relics was evaluated. This study provides a scientific basis and experimental data for the application of polymeric adhesives in the conservation of paper relics.