A material comprising a polyester carrier with one or more coatings, a release layer and an adhesive layer. The foil is transferred – generally by heat – onto paper, and the carrier is stripped away, leaving the coating bonded to the substrate by the adhesive. This coating can be plain or imaged, monochrome or coloured, colour-shifting, iridescent, metallised, holographic, etc. Also known as hot stamping or transfer foil. Foils are generally applied to banknotes as a continuous stripe (typically measuring 6-10mm wide) or a patch (typically square, circular or elliptical).