abstract |
A method of computer-to-cylinder lithographic printing, comprising: loading a plate material on a rotative plate cylinder of a lithographic printing apparatus; rotating the plate cylinder having loaded thereon the plate material; forming an image directly onto the plate material by an inkjet image-recording process which comprises ejecting an oil-based ink from a recording head having a plurality of ejecting channels, based on image data signals, utilizing an electrostatic field, to prepare a printing plate; subsequently performing lithographic printing with the thus prepared printing plate, wherein the recording head is driven so that every n'th channel thereof is actuated in a common phase, and wherein the plate cylinder is rotated to give a surface rotational speed V (mm/sec) of the plate material as represented by the following formula:wherein N represents a recording resolution (dots/25.4 mm) along a rotative direction of the plate cylinder on the plate material, and f represents a driving frequency f (Hz) of each ejecting channel of the recording head. |