| 摘要 |
PURPOSE:To produce an excellent offset printing block by a simple scanning mechanism. CONSTITUTION:Jets of the liquid droplets for forming lipophilic patterns are directed against an offset plate material 13 from a liquid droplet injection head 16 undergoing a feed axially of a drum 11 which supports the offset plate material 13 having a hydrophilic surface on its outer peripheral surface and effects a main scanning by its rotation, the unit dots of the liquid droplets injected from the liquid droplet injection head 16 are collected in the number of N (N>=2) to form a reference dot and a control part 25 regulates the speed of the main scanning by the drum 11 according to the size of the reference dot. Furthermore, patterns are formed for binary images at a minimum unit of the reference dot through a signal arranging and converting circuit 21, unit gradation image is formed for gradation image by collecting the unit dots in the number of M (M>=2) and patterns are formed by controlling the number of the unit dots in the reference dot. |
