Offset and perfecting printing machine

PURPOSE: To provide many printing units and perfecting form print by guiding a printing image transfer element via a printing area between at least one plate cylinder and at least one opposed impression cylinder, and forming it as an endless belt-like printing image collecting element in contact with a central impression cylinder. CONSTITUTION: A sheet removed from a sheet feeder 1 is guided to a sheet inserting plate 2 and a sheet delivery unit 3 to a sheet guiding cylinder 4.1. After printing, an ink adhered to a sheet is dried by a drier 15. A printing image collecting element 7 is passed through a printing area between a printing cylinder 9 of a first printing unit and a counter-pressure cylinder 12, and a printing image is received with the first ink. It is coated with another ink similarly in response to number of the printing units. A collected ink image is transferred to the sheet in the case of passing the printing area between the guiding cylinder and the element 7. After the sheet is delivered to a backing printing impression cylinder 29.1, a rear surface of the sheet is printed by a backing printing unit 28 formed in a shape of a printing unit or another printing image collecting element.