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.
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.
Deacidification plays an important role in the conservation of paper-based cultural heritage objects. Herein, a novel approach for the conservation of scale paper-based cultural heritage objects is proposed using a mixture of argon and ethylene oxide (EO-Ar) for the first time. The optimum process conditions for deacidification of ethylene oxide and argon mixture system are determined by orthogonal testing. To evaluate the stabilization effect of paper treated with EO-Ar, the degradation of the mechanical properties (tensile strength, folding endurance and tearing strength tests) of paper after artificial aging was evaluated. The results show that the treated paper had better durability with respect to tensile strength, folding endurance and tearing strength. Additionally, thermal stability, crystallinity and fiber wall thickness increased after EO-Ar treated, which was determined by scanning electron microscope (SEM), diffraction of X-rays (XRD), and thermo gravimetric (TG) analysis. Some compounds, such as polyethylene glycol, organic acids, esters, were detected by GC-MS after treatment with EO-Ar. Two hundred and forty books including acidic, weak acidic and alkaline books were successfully deacidified, resulting in pH values of paper ranges suitable for paper preservation. Finally, a possible mechanism of deacidification of EO-Ar was proposed.
Situated in the village of Lama Temple on the eastern bank of the Wulie River in Chengde, Puren Temple stands as one of the few remaining royal temples of great importance from the Kangxi era (1662–1722 AD). This ancient edifice has greatly contributed to the advancement of our comprehension regarding the art of royal temple painting. The present study undertakes a comprehensive analysis and identification of nine samples obtained from the beams and ceiling paintings within the main hall of Puren Temple. Furthermore, a systematic examination of their mineral pigments and adhesives is conducted. The findings from polarized light microscopy (PLM), energy-type X-ray fluorescence spectrometer (ED-XRF), micro-Raman spectroscopy (m-RS), and X-ray diffractometer (XRD) analyses reveal that the pigments present in the main hall beams of Puren Temple are cinnabar, lead white, lapis lazuli, and lime green, while the pigments in the ceiling paintings consist of cinnabar, staghorn, lead white, lapis lazuli, and lime green. The use of animal glue as a binder for these pigments on both the main hall beams and ceiling paintings is confirmed via pyrolysis-gas chromatography–mass spectrometry (Py-Gc/Ms) results. These findings hold significant implications for the future restoration of Puren Temple, as they provide valuable guidance for the selection of appropriate restoration materials.
Jiatang scroll paintings listed in the Chinese intangible cultural heritage list are an important form of family trees. In this paper, a Jiatang scroll painting drawn in the seventh year of Guangxu (AD 1881) was chosen as a prototype to analyze its components. Samples were taken from different parts of the Jiatang scroll painting to analyze the composition of fibers, pigments, and adhesives. Herein, fiber analyzer, Fourier transform infrared spectroscopy (FTIR), and Herzberg stain were conducted to identify the type of fiber used. Microstructural and microchemical analyses by means of SEM-EDX and Raman spectroscopy were performed to characterize the pigments present in the painting, while the nature of the adhesive was examined using pyrolysis gas chromatography–mass spectrometry (Py-GC/MS). The results show that the painting fiber is from cotton, while the red, black, and green pigments were identified as cinnabar, carbon black, and emerald green, respectively. Finally, the adhesive is a mixture of animal glue, benzoin gum, and starch. The research results provide a basis for the protection and restoration of this precious cultural heritage in the future.
Color paintings have much aesthetic value and historical importance. This study examined the color paintings of the east pillar of the Taiping Heavenly Kingdom’s Great Hall. The pillars in interiors of ancient buildings were painted with a layer of red lacquer. The painted pillars are valuable because they symbolize the highest rank of a building’s hierarchy and the esteemed status of the owner. In this study, we investigated pigments, inorganic fillers, and adhesives used in the color paintings of the royal residence. Energy dispersive X-ray spectrometry, polarized light microscopy, and Raman spectroscopy were used to investigate the pigments of the paintings. Pyrolysis–gas chromatography–mass spectrometry (Py–GC/MS) was used to classify the composition of adhesives. The results showed that the painted pigments included vermilion (HgS), graphite (C), white lead (2PbCO3·Pb(OH)2), and lead red (Pb3O4). The Py–GC/MS showed possible presence of tung oil and flour in the mortar. The X-ray diffraction demonstrated the presence of limewater and brick dust (gismondine, dolomite). The analyses of pigment, inorganic fillers, and adhesives of the Taiping royal palace paintings provide information on the long-standing preservation of the paintings.