rainbow holograms tagged posts

This is an example of an inkjet printed rainbow hologram. Credit: ITMO University

This new method is expected to significantly reduce the cost and time needed to create the so-called rainbow holograms, commonly used for security purposes – to protect valuable items, such as credit cards and paper currency, from piracy and falsification.

The team, led by Alexander Vinogradov, SCAMT in ITMO University, developed colorless ink made of nanocrystalline titania, which can be loaded into an inkjet printer and then deposited on special microembossed paper, resulting in unique patterned images. The ink makes it possible to print custom holographic images on transparent film in a matter of minutes, instead of days as with the use of conventional methods.

“The conventional way of preparing a rainbow ...