Application and Challenges of Chinese Lacquer Identification Techniques in the Conservation of Cultural Relics

Chinese lacquer, a natural polymer with exceptional durability and cultural significance, has been widely used since the Warring States period. This review examines recent advances in lacquer identification techniques and their role in cultural heritage conservation. Drawing on five representative case studies—the B54 Japanese armor, Ba lacquerware from Lijiaba, a Qing Dynasty folding fan, Ryukyu lacquerware, and late Joseon objects—we show how integrated analytical approaches combining microscopy, spectroscopy, chromatography, and biochemical methods provide critical insights into composition, degradation, and conservation strategies. Key findings highlight (1) the effectiveness of multi-technique analysis in characterizing complex lacquer–metal interfaces and layered structures; (2) the recognition of regional and chronological variations in lacquer formulations, highlighting the need for standardized authentication protocols and shared databases; and (3) the promise of non-destructive technologies to reduce sampling and improve aging simulations. By critically synthesizing these case studies, the review highlights both methodological successes and persistent challenges, such as ethical constraints of sampling and limited understanding of long-term degradation. Ultimately, lacquer is positioned at the intersection of material science and cultural preservation, offering a transferable framework for global heritage protection. Future directions include hyperspectral imaging, bioinspired consolidants, and computational modeling to advance non-invasive diagnostics and sustainable conservation.