Photosensitive printing form for a flexographic printing method comprising visible and non-printable information, and method for preparing such a printing form

A process for manufacturing a photosensitive flexographic printing form, the process comprising the following steps:

• a) preparing a rasterized 1-bit image file from at least one file of graphical and/or textual content to be printed, the rasterized 1-bit image file defining a first series of relief patterns and a second series of relief patterns;
• b) processing, using the rasterized 1-bit image file, the flexographic printing form to create:
• the first series of relief patterns borne by a base in an image area of the flexographic printing form, the first series of relief patterns representing the graphical and/or textual content to be printed and having a first elevation with respect to the base;
• and
• the second series of relief patterns borne by the base outside of the image area and having one or more elevations lower than the first elevation with respect to the base.