PURPOSE: To perform ink washing work in an extremely easy manner by providing a drive means for reciprocally driving an ink nozzle and a water nozzle along an ink receiving plate.

CONSTITUTION: A master cylinder 7 having a paper plate 2 wound therearound and a blanket cylinder 8 are connected to a motor to be provided in a main body 1 in a freely rotatable manner. An ink sump part 10 is provided in the vicinity of the master cylinder 7 and an ink receiving plate 15 is provided in opposed relation to a kneading roller 1 so as to provide a predetermined gap from the roller 11. The ink nozzle 19 connected to an ink supply part so that the tip thereof is turned to the ink receiving plate 15 and the water nozzle 20 connected to a water supply part so that the tip thereof is turned to the ink receiving plate 15 are provided and a drive means reciprocally driving both nozzles 19, 20 along the ink receiving plate 15 is provided and an ink drain part 21 is arranged under the ink receiving plate 15. The water nozzle 20 is provided so as to be freely reciprocally driven in the direction crossing the axial direction of the master cylinder 7 at right angles and the ink receiving plate 15 is provided so as to be freely reciprocally driven in the direction crossing the axial direction of the kneading roller 11 at right angles.