PURPOSE: To prevent a sealing machine and a material to be sealed from being soiled by ink by providing an ink cross leak preventing plate so that its wedge top forms a gap in parallel with both end surfaces of a rotary roller and the plate closely adheres to the end surfaces of an ink supply adjusting block corresponding to both inner ends of the rotary roller.

CONSTITUTION: Ink flows from the surface of an ink supply adjusting block 3 to a parallel fine gap 6 formed with the top 3a of the ink supply adjusting block and the surfaces of a rotary roller 2, and is supplied to a rotary roller surface 3c. The flowing area of the ink is limited to the central roller surface except both ends of the rotary roller 2. Consequently, a smaller amount of the ink attaching to the roller surface flows into both end surfaces 2a of the rotary roller. The top 15a of an ink cross leak preventing plate 15 is arranged so that it forms the fine gap in parallel with both end surfaces of the rotary roller 2. Consequently, even if the ink attaching to the roller surface of the rotary roller 2 flows in the cross direction of the surface of the rotary roller, it is scraped away by the top 15a of the ink cross leak preventing plate 15, and therefore it does not flow up to the end surface 2a of the rotary roller 2.