In recent years, many central banks have upgraded both security and durability when issuing new notes, including polymer substrates, dual windows, color-shifting foil, and high-durability paper. These designs extend note life and also change feel and thickness during authentication, sorting, and bundling.
Cash handlers say uneven compression can curl the edges of new notes. Stable pressure sensing and heat-pressed sealing help keep the appearance of new series intact.
Banks and cash centers need equipment that can handle mixed thickness and materials so operations stay on pace during changeover.