Iridescent printed features for designs that appear or disappear in the light
Iridescent printed features use a brilliant ink that changes color when the banknote is tilted to make designs appear or disappear in the light. The iridescent effect is visible or invisible depending on the angle of incidence of the light that hits the banknote. These anti-copying optically variable features are popular for use in upgrading the security of an existing banknote design.
Iridescent features are versatile and enable more in-depth visual verification of banknote authenticity without the need for special devices. The iridescent effect is the result of tiny shimmering pads made of mica combined with a transparent ink varnish. If this ink varnish is applied to a substrate using the silkscreen process, the formation adopted by the pads generates the visible iridescent effect.
Iridescent features can be printed in perfect register to the banknote both horizontally and vertically for optimum integration into any banknote design. Available in a wide range of colors, iridescent features can be registered as a patch, as a continuous stripe, or in combination together, to the note.
Adding UV pigments to the iridescent ink produces a different appearance in daylight or in UV light to create a further barrier against counterfeiting.