To provide a method and an apparatus for on-press imaging lithographic printing having no bleeding, high resolution and stable drive by lowering a signal voltage 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 forming an electrostatic field based on a signal of image data at the unit in a state in which the ink of the unit is irradiated with a light to fly the ink from the unit in an ink jet type to form the image of the plate.
OSAWA SADAO
ISHII KAZUO
KATO EIICHI
