| abstract |
The present invention relates to the field of security inks suitable for printing machine readable security features on substrate, security documents or articles as well as machine readable security feature made from said security inks, and security documents comprising a machine readable security feature made from said security inks. In particular, the invention provides security inks comprising one or more IR absorbing materials wherein said security ink allows the production of a machine readable security feature having the following optical properties: a lightness L* equal to or higher than about 80, a chroma C* smaller than or equal to about 15 and a reflectance at 900 nm smaller than or equal to about 60%. |