Research on the Restoration of Red Sandalwood Frame Hanging Screen with Dyed Ivory Inlay from Qing Dynasty in the Palace Museum

The red sandalwood frame hanging screen with dyed ivory inlays (the Palace Museum collection) is a typical cultural relic from the Qing Dynasty, and it was created based on an imitation painting painted by Emperor Qianlong. Currently, the hanging screen needs immediate restoration due to the dustiness of the surface and the loose, discoloration, and missing of inlays. Before restoration, the inlaid materials and dyes were analyzed using optical microscopy, Raman spectroscopy, infrared spectroscopy, and ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry. The results show that the inlaid materials were mainly ivory and lapis lazuli, and the dyes of the ivory are cinnabar, carthamin, and brilliant crocein. The inlaid lapis lazuli was re-coloured using natural lapis lazuli mineral pigments. Based on these results, a targeted restoration plan was developed, including colour fixation, dust removal, and inlays complement, etc. The research on the restoration of the hanging screen not only provides a valuable reference for the future restoration of dyed ivory objects, but also contributes insights into the research on imperial imitation painting and cross-material transformation and the preservation of related Qing court artifacts.