Direct Answer
Tactile features are raised geometric patterns (like lines or dots) printed using heavy intaglio ink on the edges of banknotes to help visually impaired individuals feel the denomination
Cotton-Paper Issue
Cotton absorbs human sweat, oil, and atmospheric moisture. This softens the fibers, causing the raised ink features to flatten out and disappear after a few months of active circulation.Polymer Solution
Plastic is entirely non-porous and rigid. It repels moisture and oils, meaning the heavily embossed tactile dots/lines retain their sharp, raised structure for years.
Cotton absorbs human sweat, oil, and atmospheric moisture. This softens the fibers, causing the raised ink features to flatten out and disappear after a few months of active circulation.Polymer Solution
Plastic is entirely non-porous and rigid. It repels moisture and oils, meaning the heavily embossed tactile dots/lines retain their sharp, raised structure for years.