Patent ID: 7677171

Claim:
A process for printing successive sheets of documents, such as securities, banknotes, checks, ID and passports, the process comprising the steps of: transporting the successive sheets by a chain gripper system including successive grippers attached to two parallel chains, providing a printing unit including a printing cylinder with at least one transversal cylinder pit, wherein the successive sheets are printed in said printing unit while being held by the chain gripper system, and wherein the chain gripper system has a chain speed V c and the printing cylinder has a printing cylinder speed V pc , wherein the chain speed V c and the printing cylinder speed V pc are synchronized such that a gripper of the chain gripper system enters said cylinder pit at a trailing edge of said printing cylinder, wherein said chain speed V c and said printing cylinder speed V pc are then relatively modified such that said gripper arrives at a leading end of said printing cylinder when ink starts to be deposited on the sheet being printed.