Extraction percentage analysis of inkpad seals stored under different conditions

摘要

Inkpad seals are often placed on important documents in China. Determining the date when a seal was affixed can be important in assessing the authenticity of a document. In this paper, an extraction percentage analysis method was employed to date the inkpad seals. Calibration curves were created to express the relationship between the extraction percentage of inkpad seal components and the age of inkpad seal entries stored under heat (thermal) ageing and UV-induced ageing conditions. The correspondence between the natural ageing, heat ageing and UV-induced ageing conditions was also established.