Observation of in-plane moisture distribution of a drying process using terahertz waves

Abstract

The amount of moisture in the ink and the particle structure of the colorant have a significant effect on image quality. In recent years, demand for functional films with strong coating strength and electrical conductivity has been increasing, but many types of functional films are difficult to observe inside the coating by visible light. In this paper, we investigate the relationship between the transmitted terahertz wave intensity and the amount of moisture by using the absorption of terahertz waves in water. We then demonstrate the validity of our method using pulp paper with a small amount of moisture.