Watermark inks for printing

Watermark inks are inks used for printing watermarks visible after illuminating the prints from behind.

These inks imitate watermarks used in production of papers protected from forgery and copying.

In areas printed with the ink imitating a watermark, a high transparency of the substrate is obtained, which resembles the original watermark integrated into the security paper.

Due to the migration of ink, it is recommended to use offset papers with a high substrate porosity.

Because these inks are rather oily, it is advised to print the back side of a substrate and avoid overprinting with other inks.

The best results are obtained by using a highly porous offset paper with a grammage lower than 90 g/m². 

As the inks imitating watermarks are a very simple and functional security of authenticity of documents, they are used in printing securities such as: cheques, gift vouchers, coupons as well as tickets and lottery tickets.