To provide a method and an apparatus for on-press imaging lithographic printing having no bleeding, high resolution and stable drive at a low cost and capable of dealing with digital without necessity of developing process by using a high speed ink jet type easy to form a line head.
The method for on-press imaging lithographic printing comprises the steps of mounting a plate material on the plate cylinder of a printer, directly forming an image on the material based on a signal of image data to form a press plate, using the plate in its state and subsequently printing the lithographic plate. This method further comprises the steps of supplying an oil based ink to a discharge unit disposed oppositely to the material mounted on the cylinder, and irradiating the ink with a light in a state in which an electrostatic field is formed at the unit to fly the ink from the unit to form the image of the plate in the ink jet type.
OSAWA SADAO
ISHII KAZUO
KATO EIICHI
